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All questions of Science for Class 9 Exam
Direction: The distance moved by a student at different intervals of time, while walking to school, is given in the table below.A distance time graph for the motion of the student is also shown. Study the table and the graph and choose correct options to answer any four questions given below:
Q. What will be the speed if the body travels a distance of 15 metres in 10 seconds?- a)0.5 m/s
- b)1.5 m/s
- c)5 m/s
- d)10 m/s
Correct answer is option 'B'. Can you explain this answer?
Direction: The distance moved by a student at different intervals of time, while walking to school, is given in the table below.
A distance time graph for the motion of the student is also shown. Study the table and the graph and choose correct options to answer any four questions given below:
Q. What will be the speed if the body travels a distance of 15 metres in 10 seconds?
a)
0.5 m/s
b)
1.5 m/s
c)
5 m/s
d)
10 m/s
|
|
Piyush answered |
Speed = Distance/Time
=15/10 = 1.5 m/s
=15/10 = 1.5 m/s
Direction: Read the following and answers the questions.A homogeneous mixture of two or more substances called a true solution. it consists of solute and solvent. The particle size of true solution in less than 1 nanometer. A suspension is a heterogeneous mixture in which the solute particle does not dissolve but remain suspended throughout the bulk of the medium. A colloid is a mixture that is actually heterogeneous but appears to be homogeneous as the particles are uniformly spread throughout the solution.Q. Which statement is incorrect about Tyndall effect.- a)True solution show Tyndall effect
- b)Suspensions show Tyndall effect
- c)Colloid show Tyndall effect
- d)Both B and C show Tyndall effect
Correct answer is option 'D'. Can you explain this answer?
Direction: Read the following and answers the questions.
A homogeneous mixture of two or more substances called a true solution. it consists of solute and solvent. The particle size of true solution in less than 1 nanometer. A suspension is a heterogeneous mixture in which the solute particle does not dissolve but remain suspended throughout the bulk of the medium. A colloid is a mixture that is actually heterogeneous but appears to be homogeneous as the particles are uniformly spread throughout the solution.
Q. Which statement is incorrect about Tyndall effect.
a)
True solution show Tyndall effect
b)
Suspensions show Tyndall effect
c)
Colloid show Tyndall effect
d)
Both B and C show Tyndall effect
|
Swati Verma answered |
Tyndall effect, also called Tyndall phenomenon, scattering of a beam of light by a medium containing small suspended particles. E.g., smoke or dust in a room, which makes visible a light beam entering a window. The effect is named for the 19th-century British physicist John Tyndall, who first studied it extensively.
Direction: Observe the diagram and answer any four questions below:Two forces F1 = 20 N and F2 = 30 N are acting on an object as shown in figure :
Q. Find the net force acting on the object.- a)Zero
- b)30 N
- c)20 N
- d)10 N
Correct answer is option 'D'. Can you explain this answer?
Direction: Observe the diagram and answer any four questions below:
Two forces F1 = 20 N and F2 = 30 N are acting on an object as shown in figure :
Q. Find the net force acting on the object.
a)
Zero
b)
30 N
c)
20 N
d)
10 N
|
Mirza Baksh answered |
F2-F2 = 10N
Direction: 75 kg missile is dropped downwards from an air plane, and has a speed of 60 m/s at an altitude of 850 m above the ground. Determine:(a) The K.E. possessed by the missile at 850 m.(b) The P.E. possessed by the missile at 850 m.(c) The total mechanical energy possessed by the missile.(d) The K.E. and velocity with which it strikes the ground.Q. The K.E. and velocity with which it strikes the ground.- a)135000 J
- b)637500 J
- c)772500 J
- d)635700 J
Correct answer is option 'C'. Can you explain this answer?
Direction: 75 kg missile is dropped downwards from an air plane, and has a speed of 60 m/s at an altitude of 850 m above the ground. Determine:
(a) The K.E. possessed by the missile at 850 m.
(b) The P.E. possessed by the missile at 850 m.
(c) The total mechanical energy possessed by the missile.
(d) The K.E. and velocity with which it strikes the ground.
Q. The K.E. and velocity with which it strikes the ground.
a)
135000 J
b)
637500 J
c)
772500 J
d)
635700 J
|
Meera Rana answered |
K.E. at the ground = 7.7 × 105J K.E. = 1 /2 mv2,
Therefore, v2 = 2 K.E. / m
Velocity with which missile strikes the ground = 143.2 m/s.
Direction: The electronic configuration of an element ‘X’ is 2, 8, 2 :Q. How many Valence electrons are there in element X?- a)2
- b)3
- c)8
- d)10
Correct answer is option 'A'. Can you explain this answer?
Direction: The electronic configuration of an element ‘X’ is 2, 8, 2 :
Q. How many Valence electrons are there in element X?
a)
2
b)
3
c)
8
d)
10
|
|
Swati Verma answered |
The element present in the outermost shell are known as Valence electrons. In the outermost shell of element X 2 Valence electrons are present.
Direction: Read the following and answers the questions.A homogeneous mixture of two or more substances called a true solution. it consists of solute and solvent. The particle size of true solution in less than 1 nanometer. A suspension is a heterogeneous mixture in which the solute particle does not dissolve but remain suspended throughout the bulk of the medium. A colloid is a mixture that is actually heterogeneous but appears to be homogeneous as the particles are uniformly spread throughout the solution.Q. Which one of the following is most stable? - a)True solution
- b)Suspensions
- c)Colloids
- d)Both A and B
Correct answer is option 'A'. Can you explain this answer?
Direction: Read the following and answers the questions.
A homogeneous mixture of two or more substances called a true solution. it consists of solute and solvent. The particle size of true solution in less than 1 nanometer. A suspension is a heterogeneous mixture in which the solute particle does not dissolve but remain suspended throughout the bulk of the medium. A colloid is a mixture that is actually heterogeneous but appears to be homogeneous as the particles are uniformly spread throughout the solution.
Q. Which one of the following is most stable?
a)
True solution
b)
Suspensions
c)
Colloids
d)
Both A and B
|
|
Swati Verma answered |
A true solution is a homogeneous mixture of two or more substances in which the particle size of the material dissolved (solute) in the solvent is less than 10-9 m or 1 nm. True solution is exemplified by a simple sugar solution in water
Direction: Read the following and answers the questions.A homogeneous mixture of two or more substances called a true solution. it consists of solute and solvent. The particle size of true solution in less than 1 nanometer. A suspension is a heterogeneous mixture in which the solute particle does not dissolve but remain suspended throughout the bulk of the medium. A colloid is a mixture that is actually heterogeneous but appears to be homogeneous as the particles are uniformly spread throughout the solution.Q. Which is the correct order of stability of solution- a)True < colloid="" />< />
- b)Colloid < suspension="" />< />
- c)Colloid < true="" />< />
- d)Suspension < colloid="" />< />
Correct answer is option 'D'. Can you explain this answer?
Direction: Read the following and answers the questions.
A homogeneous mixture of two or more substances called a true solution. it consists of solute and solvent. The particle size of true solution in less than 1 nanometer. A suspension is a heterogeneous mixture in which the solute particle does not dissolve but remain suspended throughout the bulk of the medium. A colloid is a mixture that is actually heterogeneous but appears to be homogeneous as the particles are uniformly spread throughout the solution.
Q. Which is the correct order of stability of solution
a)
True < colloid="" />< />
b)
Colloid < suspension="" />< />
c)
Colloid < true="" />< />
d)
Suspension < colloid="" />< />
|
|
Meera Rana answered |
- Suspension: Common examples of suspension include the mixture of chalk and water, muddy water, the mixture of flour and water, a mixture of dust particles and air, fog, milk of magnesia, etc.
- A colloid is a mixture in which one substance of microscopically dispersed insoluble particles are suspended throughout another substance.
- True solution is a homogeneous mixture of two or more substances. A true solution is a homogeneous mixture with uniform properties throughout.
Direction: Read the given situations and answer the following questions.(i) Seema of class IX was having common cold. She sits with Sarika who also develops the disease.(ii) Meena of class IX shifted to a new residence, with his family, where water purification system has not been installed yet. He develops cholera and dysentery.Q. What type of food you have to take when you are sick?- a)Junk food
- b)Spicy and Oily food
- c)Blend and nourishing food
- d)Liquid food.
Correct answer is option 'C'. Can you explain this answer?
Direction: Read the given situations and answer the following questions.
(i) Seema of class IX was having common cold. She sits with Sarika who also develops the disease.
(ii) Meena of class IX shifted to a new residence, with his family, where water purification system has not been installed yet. He develops cholera and dysentery.
Q. What type of food you have to take when you are sick?
a)
Junk food
b)
Spicy and Oily food
c)
Blend and nourishing food
d)
Liquid food.
|
|
Meera Rana answered |
Blend and nourishing food provides adequate amount of nutrients required for regeneration of cells and tissues.
Direction: In each of the following questions, a statement of Assertion is given and a corresponding statement of Reason is given just below it. Of the statements, given below, mark the correct answer as:Assertion : Its okay to sit near a person suffering from cold.Reason : Cold is a non-communicable disease.- a)Both assertion and reason are true and reason is the correct explanation of assertion.
- b)Both assertion and reason are true but reason is not the correct explanation of assertion.
- c)Assertion is true but reason is false.
- d)Both Assertion and Reason are false.
Correct answer is option 'D'. Can you explain this answer?
Direction: In each of the following questions, a statement of Assertion is given and a corresponding statement of Reason is given just below it. Of the statements, given below, mark the correct answer as:
Assertion : Its okay to sit near a person suffering from cold.
Reason : Cold is a non-communicable disease.
a)
Both assertion and reason are true and reason is the correct explanation of assertion.
b)
Both assertion and reason are true but reason is not the correct explanation of assertion.
c)
Assertion is true but reason is false.
d)
Both Assertion and Reason are false.
|
Dont Memorise answered |
It is not okay to sit near a person suffering from cold because cold is a communicable disease. The droplets containing the causative microbe of cold can spread through air when the person sneezes or coughs. If someone standing close by and breathes in these droplets, a person might get infected.
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion: Sudden application of brakes in a moving car may cause injury.Reason: Inertia is the tendency of an object to keep moving or being at rest undisturbed.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
Correct answer is option 'B'. Can you explain this answer?
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion: Sudden application of brakes in a moving car may cause injury.
Reason: Inertia is the tendency of an object to keep moving or being at rest undisturbed.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
|
|
Swati Verma answered |
When we are in a moving car, our body is also moving with the velocity of car. Sudden brake applied stops the car as well as lower body portion while upper body portion is still in motion that causes injury.
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion: Electron move away from a region of higher potential to a region of lower potential.
Reason: An electron has a negative charge.
- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
Correct answer is option 'D'. Can you explain this answer?
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion: Electron move away from a region of higher potential to a region of lower potential.
Reason: An electron has a negative charge.
Assertion: Electron move away from a region of higher potential to a region of lower potential.
Reason: An electron has a negative charge.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
|
|
Swati Verma answered |
Direction of electric field is from region of high potential to low potential & electron or any -ve charged particle will move against the field or lower potential to higher potential.
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : The size of the nucleus is very small as compared to the size of the atom.Reason : The electrons revolve around the nucleus of the atom.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
Correct answer is option 'B'. Can you explain this answer?
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : The size of the nucleus is very small as compared to the size of the atom.
Reason : The electrons revolve around the nucleus of the atom.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
|
Avinash Patel answered |
The nucleus of an atom is about 10-15 m in size; this means it is about 10-5 (or 1/100,000) of the size of the whole atom. A good comparison of the nucleus to the atom is like a pea in the middle of a racetrack. (10-15 m is typical for the smaller nuclei; larger ones go up to about 10 times that.)
Direction : In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : An object thrown vertically upward with certain velocity v, reaches maximum height and fall back with same velocity.Reason : Whenever an object falls towards the earth, gravitational force of the earth causes acceleration.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
Correct answer is option 'D'. Can you explain this answer?
Direction : In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : An object thrown vertically upward with certain velocity v, reaches maximum height and fall back with same velocity.
Reason : Whenever an object falls towards the earth, gravitational force of the earth causes acceleration.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
|
Vivek Rana answered |
When an object is thrown vertically upward with certain velocity, it will fall back freely. There will be a change in the magnitude of velocity due gravitational force of the earth.
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion: Epithelial tissues are covering or protective tissues.Reason: Materials are exchanged at the surface across the epithelial tissues.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
Correct answer is option 'B'. Can you explain this answer?
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion: Epithelial tissues are covering or protective tissues.
Reason: Materials are exchanged at the surface across the epithelial tissues.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
|
|
Aditya Shah answered |
Epithelial tissue forms a continuous layer over the free surfaces of many other tissues. Consequently, it covers the external surface of the animal body and the internal (luminal) surfaces of visceral organs, body cavities and blood vessels. Thus, it protects the underlying and overlying tissues. Another important function of epithelial tissue is exchange of materials.
Direction: Study the diagram of a plan cell and answer the following Questions-
Q. The special structures in plant cell known as Kitchen of the Cell- a)Ribosomes
- b)Cytoplasm
- c)Lysosomes
- d)Chloroplast
Correct answer is option 'D'. Can you explain this answer?
Direction: Study the diagram of a plan cell and answer the following Questions-
Q. The special structures in plant cell known as Kitchen of the Cell
a)
Ribosomes
b)
Cytoplasm
c)
Lysosomes
d)
Chloroplast
|
|
Aditya Shah answered |
Plants contains Plastids and Chloroplast is a type of Plastid where photosynthesis take place.
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion: Bone and cartilage are connective tissue.
Reason: Blood is connective tissue in which plasma is the matrix.
- a)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
Correct answer is option 'B'. Can you explain this answer?
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion: Bone and cartilage are connective tissue.
Reason: Blood is connective tissue in which plasma is the matrix.
a)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
|
|
Meera Rana answered |
- Assertion (A): True. Bone and cartilage are types of connective tissue. They support and protect the body, with bone being hard and rigid, while cartilage is more flexible.
- Reason (R): True. Blood is indeed a connective tissue, and the plasma serves as its matrix, providing a medium for transporting nutrients, waste, and cells.
- The reason does not explain why bone and cartilage are connective tissues; it describes blood instead.
Thus, the correct choice is A: Both assertion and reason are true, but reason is not the correct explanation of assertion.
- Reason (R): True. Blood is indeed a connective tissue, and the plasma serves as its matrix, providing a medium for transporting nutrients, waste, and cells.
- The reason does not explain why bone and cartilage are connective tissues; it describes blood instead.
Thus, the correct choice is A: Both assertion and reason are true, but reason is not the correct explanation of assertion.
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Chloroplast performs photosynthesis.Reason : Chloroplast comprises photosynthetic pigments.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
Correct answer is option 'A'. Can you explain this answer?
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Chloroplast performs photosynthesis.
Reason : Chloroplast comprises photosynthetic pigments.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
|
Radha Iyer answered |
Chloroplast is involved in the process of photosynthesis. It comprises a photosynthetic pigment called chlorophyll, which trap energy from the Sun.
Direction: Some of the action like moving our limbs , fingers, moving neck etc. can be controlled by our will. These parts of body we can move by our own will but some actions like blinking of eyes, contraction and relaxation of heart are not controlled by our actions.Q. Muscles which are found in Heart :- a)Smooth
- b)Cardiac
- c)Striated
- d)All of these
Correct answer is option 'B'. Can you explain this answer?
Direction: Some of the action like moving our limbs , fingers, moving neck etc. can be controlled by our will. These parts of body we can move by our own will but some actions like blinking of eyes, contraction and relaxation of heart are not controlled by our actions.
Q. Muscles which are found in Heart :
a)
Smooth
b)
Cardiac
c)
Striated
d)
All of these
|
|
Radha Iyer answered |
- Cardiac muscles are cylindrical, uninucleated and branched involuntary muscles found in the heart.
- Cardiac muscle tissue is one of the three types of muscle tissue in your body. The other two types are skeletal muscle tissue and smooth muscle tissue.
- Cardiac muscle tissue is only found in your heart, where it performs coordinated contractions that allow your heart to pump blood through your circulatory system.
Direction: Read the passage and answer the questions given, one mark questions.Anything that occupies some space, having mass, volume and can be felt by one or more out of five senses is called matter. The purest form of matter is called an element. An element is a substance which cannot be split up into two or more simpler substances by the usual chemical methods of applying heat, light or electric energy.A pure substance consists of a single type of particles. All the elements and compounds are pure substances because they contain only one kind of particles. eg. Hydrogen, Carbon, Oxygen, Carbon-monoxide, Copper, Gold, Silver. A pure substance has a fixed composition as well as a fixed boiling point and melting point. The presence of impurities generally increases the melting and boiling point of the pure substancesQ. The boiling point of pure water is 100oC. What likely be the effect on the boiling point of water if 150 gm NaCl is added to one litre water.- a)Increases
- b)Decreases
- c)Remain same
- d)Does not effected
Correct answer is option 'A'. Can you explain this answer?
Direction: Read the passage and answer the questions given, one mark questions.
Anything that occupies some space, having mass, volume and can be felt by one or more out of five senses is called matter. The purest form of matter is called an element. An element is a substance which cannot be split up into two or more simpler substances by the usual chemical methods of applying heat, light or electric energy.
A pure substance consists of a single type of particles. All the elements and compounds are pure substances because they contain only one kind of particles. eg. Hydrogen, Carbon, Oxygen, Carbon-monoxide, Copper, Gold, Silver. A pure substance has a fixed composition as well as a fixed boiling point and melting point. The presence of impurities generally increases the melting and boiling point of the pure substances
Q. The boiling point of pure water is 100oC. What likely be the effect on the boiling point of water if 150 gm NaCl is added to one litre water.
a)
Increases
b)
Decreases
c)
Remain same
d)
Does not effected
|
|
Aditya Shah answered |
On adding salt to the water, its freezing decreases and boiling point increases because of the effect of Van't Hoff factor, i; for NaCl the value of i = 2.
Direction : In each of the following questions, a statement of Assertion is given and a corresponding statement of Reason is given just below it. Of the statements, given below, mark the correct answer as:Assertion : At the centre of earth, a body has a centre of mass but no centre of gravity.Reason : Acceleration due to gravity at the centre of the earth is zero.- a)Both assertion and reason are true and reason is the correct explanation of assertion.
- b)Both assertion and reason are true but reason is not the correct explanation of assertion.
- c)Assertion is true but reason is false.
- d)Both Assertion and Reason are false.
Correct answer is option 'A'. Can you explain this answer?
Direction : In each of the following questions, a statement of Assertion is given and a corresponding statement of Reason is given just below it. Of the statements, given below, mark the correct answer as:
Assertion : At the centre of earth, a body has a centre of mass but no centre of gravity.
Reason : Acceleration due to gravity at the centre of the earth is zero.
a)
Both assertion and reason are true and reason is the correct explanation of assertion.
b)
Both assertion and reason are true but reason is not the correct explanation of assertion.
c)
Assertion is true but reason is false.
d)
Both Assertion and Reason are false.
|
|
Anita Menon answered |
At the centre of the earth value of g is zero, weight of the body is also zero but its mass remains the same. The centre of mass of the body thus remains unchanged.
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Atom is electrically neutral.Reason : A neutral particle, neutron is present in the nucleus of atom.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
Correct answer is option 'B'. Can you explain this answer?
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Atom is electrically neutral.
Reason : A neutral particle, neutron is present in the nucleus of atom.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
|
|
Aditi Sharma answered |
Atom is electrically neutral because the number of protons (positively charged particle) is equal to the number of electrons (negatively charged particle).
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Permanent tissue is composed of mature cells.Reason : Meristematic tissue is a group of actively dividing cells.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
Correct answer is option 'A'. Can you explain this answer?
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Permanent tissue is composed of mature cells.
Reason : Meristematic tissue is a group of actively dividing cells.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
|
|
Ananya Das answered |
A meristematic tissue is a group of cells. That are in a continuous state of division or retain their power of division. Permanent tissues are composed of mature cells that, after undergoing complete growth, have assumed a definite shape, size and function and have temporarily or permanently lost the power of division.
Direction : In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Mass of an object is always zero.Reason : Mass of an object is the measure of its inertia and the substance contained by the body.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
Correct answer is option 'D'. Can you explain this answer?
Direction : In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Mass of an object is always zero.
Reason : Mass of an object is the measure of its inertia and the substance contained by the body.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
|
|
Aditi Sharma answered |
Mass of an object can never be zero because mass of an object is the measure of its inertia and the substance contained by the body.
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Parenchyma cells help in storage of food.Reason : Parenchyma cells are the main seats of photosynthesis.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
Correct answer is option 'B'. Can you explain this answer?
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Parenchyma cells help in storage of food.
Reason : Parenchyma cells are the main seats of photosynthesis.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
|
|
Swati Verma answered |
The functions of the parenchymatous tissue is store food material in the form of starch, proteins, oils and fats. The parenchymatous tissues in root and stem tubers are good examples. The xylem and phloem parenchyma also store starchy food. The parenchymatous cells that contain chloroplasts are the main seats of photosynthesis, e.g., palisade cells of leaf.
Direction: Study the given diagram of bacterial cell and answer the following questions.
Q. The parts (1), (2) and (3) are- a)Nucleoid, Cell wall, Plasma membrane
- b)Plasma membrane, Cell wall, Nucleoid
- c)Nucleoid, Plasma membrane, Cell wall
- d)Cell Wall, Nucleoid, Plasma membrane
Correct answer is option 'D'. Can you explain this answer?
Direction: Study the given diagram of bacterial cell and answer the following questions.
Q. The parts (1), (2) and (3) are
a)
Nucleoid, Cell wall, Plasma membrane
b)
Plasma membrane, Cell wall, Nucleoid
c)
Nucleoid, Plasma membrane, Cell wall
d)
Cell Wall, Nucleoid, Plasma membrane
|
Learning Education answered |
It is a gel-like matrix composed of water, enzymes, nutrients, wastes, and gases and contains cell structures such as ribosomes, a chromosome, and plasmids. The cell envelope encases the cytoplasm and all its components. Unlike the eukaryotic (true) cells, bacteria do not have a membrane enclosed nucleus.
The outer structure (1) is the cell wall.
Then the genetic data(2) is nucleoid.
The second layer(3) is the plasma membrane.
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion: Bland and nourishing food should be taken when we fall sick.Reason: Such food contains fat, oil or spices. Hence, gets digested easily.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
Correct answer is option ''. Can you explain this answer?
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion: Bland and nourishing food should be taken when we fall sick.
Reason: Such food contains fat, oil or spices. Hence, gets digested easily.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
|
|
Dont Memorise answered |
We should take bland and nourishing food when we fall sick. It is because such food does not contain fat, oil or spices, hence, gets digested easily. Also, it provides sufficient energy and nutrients which are required for recovery and regeneration.
Direction: Study the given diagram and answer the following questions.
Q. Which part in the cell help in protein synthesis- a)Chloroplast
- b)Ribosomes
- c)Nucleus
- d)Lysosomes
Correct answer is option 'B'. Can you explain this answer?
Direction: Study the given diagram and answer the following questions.
Q. Which part in the cell help in protein synthesis
a)
Chloroplast
b)
Ribosomes
c)
Nucleus
d)
Lysosomes
|
|
Swati Verma answered |
Ribosomes are called protein factories because proteins are manufactured in the Ribosomes.
Direction: Study the following diagram and choose the correct options to answer any four questions given below:
In the figure below the card is flicked with a push. It was observed that the card moves ahead while coin falls in glass.
Q. Name the law which provides the definition of force.
- a)Law of conservation of mass
- b)Newton’s third law.
- c)Newton’s second law.
- d)Newton’s first law.
Correct answer is option 'D'. Can you explain this answer?
Direction: Study the following diagram and choose the correct options to answer any four questions given below:
In the figure below the card is flicked with a push. It was observed that the card moves ahead while coin falls in glass.
Q. Name the law which provides the definition of force.
a)
Law of conservation of mass
b)
Newton’s third law.
c)
Newton’s second law.
d)
Newton’s first law.
|
|
Swati Verma answered |
Correct option is D.
Direction: Read the following paragraph and choose the correct options to answer any four questions given below :A large bus and a van, both moving with a velocity of magnitude v, have a head-on-collision and both the vehicles stop after the collision. The time of the collision is 1 sec.Q. The vehicle, which experiences the greater acceleration is .....................- a)Bus and Van both
- b)Bus
- c)Van
- d)There will not be any effect on any of the vehicle
Correct answer is option 'C'. Can you explain this answer?
Direction: Read the following paragraph and choose the correct options to answer any four questions given below :
A large bus and a van, both moving with a velocity of magnitude v, have a head-on-collision and both the vehicles stop after the collision. The time of the collision is 1 sec.
Q. The vehicle, which experiences the greater acceleration is .....................
a)
Bus and Van both
b)
Bus
c)
Van
d)
There will not be any effect on any of the vehicle
|
|
Swati Verma answered |
The vehicle, which experiences the greater acceleration is van.
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Isobars are identical in chemical properties.
Reason : Isobars have same atomic number.
- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Both assertion and reason are incorrect.
Correct answer is option 'D'. Can you explain this answer?
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Isobars are identical in chemical properties.
Reason : Isobars have same atomic number.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Both assertion and reason are incorrect.
|
|
Radha Iyer answered |
Isobars are not identical in chemical properties because they have same mass number and different atomic numbers.
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : The atoms of different elements having same mass number but different atomic numbers are known as isobars.Reason : The sum of protons and neutrons, in the isobars is always different.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
Correct answer is option 'C'. Can you explain this answer?
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : The atoms of different elements having same mass number but different atomic numbers are known as isobars.
Reason : The sum of protons and neutrons, in the isobars is always different.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
|
|
Avinash Patel answered |
Sum of protons and neutrons is known as mass number which is same for isobars.
Direction: 75 kg missile is dropped downwards from an air plane, and has a speed of 60 m/s at an altitude of 850 m above the ground. Determine:(a) The K.E. possessed by the missile at 850 m.(b) The P.E. possessed by the missile at 850 m.(c) The total mechanical energy possessed by the missile.(d) The K.E. and velocity with which it strikes the ground.Q. The K.E. possessed by the missile at 850 m.- a)1350 J
- b)135000 J
- c)153000 J
- d)1350 J
Correct answer is option 'B'. Can you explain this answer?
Direction: 75 kg missile is dropped downwards from an air plane, and has a speed of 60 m/s at an altitude of 850 m above the ground. Determine:
(a) The K.E. possessed by the missile at 850 m.
(b) The P.E. possessed by the missile at 850 m.
(c) The total mechanical energy possessed by the missile.
(d) The K.E. and velocity with which it strikes the ground.
Q. The K.E. possessed by the missile at 850 m.
a)
1350 J
b)
135000 J
c)
153000 J
d)
1350 J
|
|
Swati Verma answered |
Given
Mass of the missile, m = 75 kg and Speed, v = 60 m/s
Therefore, K.E. = 1/ 2 mv2 = 1 /2 × 75 × 60 × 60 = 13500 J.
Direction: Study the given diagram and answer the following questions.
Q. Identify the diagram- a)Plant cell
- b)Animal Cell
- c)Bacterial Cell
- d)None of these
Correct answer is option 'B'. Can you explain this answer?
Direction: Study the given diagram and answer the following questions.
Q. Identify the diagram
a)
Plant cell
b)
Animal Cell
c)
Bacterial Cell
d)
None of these
|
|
Swati Verma answered |
Animal cells do not have cell walls because they do not need them. Cell walls, which are found in plant cells, maintain cell shape, almost as if each cell has its own exoskeleton. This rigidity allows plants to stand upright without the need for bones.
Direction: Study the given diagram of bacterial cell and answer the following questions.
Q. Nearly bacteria are motile due to the presence of ___________.- a)Cilia
- b)Pseudopodia
- c)Flagella
- d)Flagella
Correct answer is option 'A'. Can you explain this answer?
Direction: Study the given diagram of bacterial cell and answer the following questions.
Q. Nearly bacteria are motile due to the presence of ___________.
a)
Cilia
b)
Pseudopodia
c)
Flagella
d)
Flagella
|
|
Swati Verma answered |
Nearly half of the bacteria are motile due to the presence of flagella. These are long, thin, helical appendages.
Direction: Read the following and answer any four questions from (i) to (v).Manish and Nitish are provided with mixture of camphor, common salt and soil by their teacher. The teacher has asked them to use the techniques of sublimation, filtration and evaporation to separate this mixture.Q. Name one more substance which can be separated from a mixture by the process of sublimation- a)Common salt
- b)Alum
- c)Ammonium chloride
- d)Both (a) & (c)
Correct answer is option 'D'. Can you explain this answer?
Direction: Read the following and answer any four questions from (i) to (v).
Manish and Nitish are provided with mixture of camphor, common salt and soil by their teacher. The teacher has asked them to use the techniques of sublimation, filtration and evaporation to separate this mixture.
Q. Name one more substance which can be separated from a mixture by the process of sublimation
a)
Common salt
b)
Alum
c)
Ammonium chloride
d)
Both (a) & (c)
|
|
Renuka Patel answered |
And (c)
Q. What techniques are Manish and Nitish supposed to use to separate the mixture?
a) Sublimation, filtration and evaporation
Q. What is sublimation?
a) Sublimation is the process in which a solid directly changes into a gas without going through the liquid state.
Q. What is filtration?
a) Filtration is a process of separating solid particles from a liquid by passing it through a porous material.
Q. What is evaporation?
a) Evaporation is the process in which a liquid changes into a gas when heated.
Q. What techniques are Manish and Nitish supposed to use to separate the mixture?
a) Sublimation, filtration and evaporation
Q. What is sublimation?
a) Sublimation is the process in which a solid directly changes into a gas without going through the liquid state.
Q. What is filtration?
a) Filtration is a process of separating solid particles from a liquid by passing it through a porous material.
Q. What is evaporation?
a) Evaporation is the process in which a liquid changes into a gas when heated.
Direction : In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Atomicity of oxygen is 2.Reason : 1 mole of an element contains 6.023 x1023 atoms.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
Correct answer is option 'B'. Can you explain this answer?
Direction : In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Atomicity of oxygen is 2.
Reason : 1 mole of an element contains 6.023 x1023 atoms.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
|
|
Swati Verma answered |
Number of atoms present in a molecule of a gaseous element is called atomicity. e.g., O2 has two atoms and hence, its atomicity is 2.
Direction: Read the following paragraph and choose the correct options to answer any four questions given below :A large bus and a van, both moving with a velocity of magnitude v, have a head-on-collision and both the vehicles stop after the collision. The time of the collision is 1 sec.Q. Under the same conditions, if there was a heavy truck heavier than the bus, in place of van, which one will be more affected?- a)Bus
- b)Truck
- c)Bus and Truck both
- d)There will not be any effect on any of the vehicle
Correct answer is option 'A'. Can you explain this answer?
Direction: Read the following paragraph and choose the correct options to answer any four questions given below :
A large bus and a van, both moving with a velocity of magnitude v, have a head-on-collision and both the vehicles stop after the collision. The time of the collision is 1 sec.
Q. Under the same conditions, if there was a heavy truck heavier than the bus, in place of van, which one will be more affected?
a)
Bus
b)
Truck
c)
Bus and Truck both
d)
There will not be any effect on any of the vehicle
|
|
Aditi Sharma answered |
Under the same conditions, if there was a heavy truck heavier than the bus, in place of van, bus will be more affected
Direction: Sunil while playing football with his friends got injured suddenly. His friends took him to the hospital and the doctor told that he was suffering from a sprain and advised bed rest. Every afternoon, his friends visited him to enquire about his health.Q. Tissue which connects bones to muscles in humans :- a)Nervous
- b)Muscular
- c)Tendons
- d)Ligaments
Correct answer is option 'C'. Can you explain this answer?
Direction: Sunil while playing football with his friends got injured suddenly. His friends took him to the hospital and the doctor told that he was suffering from a sprain and advised bed rest. Every afternoon, his friends visited him to enquire about his health.
Q. Tissue which connects bones to muscles in humans :
a)
Nervous
b)
Muscular
c)
Tendons
d)
Ligaments
|
|
Aditya Shah answered |
- A tendon is a fibrous connective tissue which attaches muscle to bones.
- A ligament is a fibrous connective tissue which attaches bone to bone, and usually serves to hold structures together and keep them stable.
Direction : In each of the following questions, a statement of Assertion is given and a corresponding statement of Reason is given just below it. Of the statements, given below, mark the correct answer as:Assertion : Any two objects in the universe attract each other by a force called gravitation force.Reason : The force of gravitation exerted by the earth is called gravity.- a)Both assertion and reason are true and reason is the correct explanation of assertion.
- b)Both assertion and reason are true but reason is not the correct explanation of assertion.
- c)Assertion is true but reason is false.
- d)Both Assertion and Reason are false.
Correct answer is option 'B'. Can you explain this answer?
Direction : In each of the following questions, a statement of Assertion is given and a corresponding statement of Reason is given just below it. Of the statements, given below, mark the correct answer as:
Assertion : Any two objects in the universe attract each other by a force called gravitation force.
Reason : The force of gravitation exerted by the earth is called gravity.
a)
Both assertion and reason are true and reason is the correct explanation of assertion.
b)
Both assertion and reason are true but reason is not the correct explanation of assertion.
c)
Assertion is true but reason is false.
d)
Both Assertion and Reason are false.
|
|
Swati Verma answered |
Gravitational acceleration is the acceleration of an object caused by the force of gravity from another object. In the absence of any other forces, any object will accelerate in a gravitational field at the same rate, regardless of the mass of the object. On the surface of the Earth, all objects fall with an acceleration of somewhere between 9.78 and 9.82m/s2 depending on latitude, with a conventional standard value of exactly 9.80665m/s2.
In a place on the earth, the acceleration due to gravity is constant because it is determined by the mass, and radius of the Earth and not the properties of the object.
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : When astronauts throw something in space, that object would continue moving in the same direction and with the same speed.Reason : The acceleration of an object produced by a net applied force is directly related to the magnitude of the force, and inversely related to the mass of the object.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
Correct answer is option 'B'. Can you explain this answer?
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : When astronauts throw something in space, that object would continue moving in the same direction and with the same speed.
Reason : The acceleration of an object produced by a net applied force is directly related to the magnitude of the force, and inversely related to the mass of the object.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
|
|
Rohit Sharma answered |
The reason and assertion is correct because the force is applied on the object is directly proportional to the mass of the object
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Leucoplasts perform photosynthesis.Reason : Chloroplasts store fats, starch and proteins.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
Correct answer is option 'D'. Can you explain this answer?
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Leucoplasts perform photosynthesis.
Reason : Chloroplasts store fats, starch and proteins.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
|
|
Samit Sahu answered |
Nothing
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Plasma membrane is selectively permeable.Reason : Plasma membrane allows some molecules to pass through it more easily than others.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
Correct answer is option 'A'. Can you explain this answer?
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Plasma membrane is selectively permeable.
Reason : Plasma membrane allows some molecules to pass through it more easily than others.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
|
|
Meera Rana answered |
Each cell is bound by an extremely delicate, thin, elastic, selectively permeable, living membrane called plasma membrane. It is selectively permeable as it allows some molecules to pass through more easily than others.
Direction: Read the following paragraph and choose the correct options to answer the questions given below:Seema was standing on a terrace of a building. She dropped a coin and a piece of paper simultaneously from the same height.Q. Which of the following statement is correct?- a)In case of a free fall, there is no change in the direction of motion of the objects.
- b)In case of a free fall, there is always a change in the direction of motion of the objects.
- c)In case of a free fall, the direction of motion reverts.
- d)None of the above statement is correct.
Correct answer is option 'A'. Can you explain this answer?
Direction: Read the following paragraph and choose the correct options to answer the questions given below:
Seema was standing on a terrace of a building. She dropped a coin and a piece of paper simultaneously from the same height.
Q. Which of the following statement is correct?
a)
In case of a free fall, there is no change in the direction of motion of the objects.
b)
In case of a free fall, there is always a change in the direction of motion of the objects.
c)
In case of a free fall, the direction of motion reverts.
d)
None of the above statement is correct.
|
|
Swati Verma answered |
In Newton physics, free fall is any motion of a body where gravity is the only force acting upon it. An object moving upwards would not normally be considered to be falling, but if it is subject to the force of gravity only, it is said to be in free fall.
Direction : In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Number of gram-molecules of SO2Cl2 in 13.5 g of sulfuryl chloride is 0.1.Reason : Gram molecular mass is equal to one gram molecule.- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
Correct answer is option 'A'. Can you explain this answer?
Direction : In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Number of gram-molecules of SO2Cl2 in 13.5 g of sulfuryl chloride is 0.1.
Reason : Gram molecular mass is equal to one gram molecule.
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
|
|
Kalyan Sen answered |
Assertion: Number of gram-molecules of SO2Cl2 in 13.5 g of sulfuryl chloride is 0.1.
Reason: Gram molecular mass is equal to one gram molecule.
Explanation:
- The gram molecular mass of a substance is the mass of one mole of that substance. It is equal to the sum of the atomic masses of all the atoms in the molecule.
- The molar mass of SO2Cl2 can be calculated by adding the atomic masses of sulfur (S), oxygen (O), and chlorine (Cl).
- The atomic masses of S, O, and Cl are 32 g/mol, 16 g/mol, and 35.5 g/mol, respectively.
- Therefore, the molar mass of SO2Cl2 is (32 + 2 * 16 + 2 * 35.5) g/mol = 135 g/mol.
- Now, to find the number of gram-molecules of SO2Cl2 in 13.5 g, we divide the given mass by the molar mass.
- Number of gram-molecules = 13.5 g / 135 g/mol = 0.1 mol.
- Hence, the assertion is true.
Explanation of Reason:
- The reason provided is correct as the gram molecular mass is indeed equal to one gram molecule.
- A gram molecule is the amount of a substance that has a mass numerically equal to its molecular mass in grams.
- Therefore, the number of gram-molecules is equal to the mass of the substance in grams divided by its molecular mass in grams per mole.
- Hence, the reason is the correct explanation of the assertion.
Conclusion:
- Both the assertion and the reason are true, and the reason correctly explains the assertion.
- Therefore, the correct answer is option 'A'.
Reason: Gram molecular mass is equal to one gram molecule.
Explanation:
- The gram molecular mass of a substance is the mass of one mole of that substance. It is equal to the sum of the atomic masses of all the atoms in the molecule.
- The molar mass of SO2Cl2 can be calculated by adding the atomic masses of sulfur (S), oxygen (O), and chlorine (Cl).
- The atomic masses of S, O, and Cl are 32 g/mol, 16 g/mol, and 35.5 g/mol, respectively.
- Therefore, the molar mass of SO2Cl2 is (32 + 2 * 16 + 2 * 35.5) g/mol = 135 g/mol.
- Now, to find the number of gram-molecules of SO2Cl2 in 13.5 g, we divide the given mass by the molar mass.
- Number of gram-molecules = 13.5 g / 135 g/mol = 0.1 mol.
- Hence, the assertion is true.
Explanation of Reason:
- The reason provided is correct as the gram molecular mass is indeed equal to one gram molecule.
- A gram molecule is the amount of a substance that has a mass numerically equal to its molecular mass in grams.
- Therefore, the number of gram-molecules is equal to the mass of the substance in grams divided by its molecular mass in grams per mole.
- Hence, the reason is the correct explanation of the assertion.
Conclusion:
- Both the assertion and the reason are true, and the reason correctly explains the assertion.
- Therefore, the correct answer is option 'A'.
Direction: In the following questions, a statement of assertion is followed by a statement of reason. Mark the correct choice as:Assertion : A light body and heavy body have same momentum. Then they also have same kinetic energy.Reason : Kinetic energy depends on mass of the body.- a)Both assertion and reason are true and reason is the correct explanation of assertion.
- b)Both assertion and reason are true but reason is not the correct explanation of assertion.
- c)Assertion is true but reason is false.
- d)Assertion is false but reason is true.
Correct answer is option 'D'. Can you explain this answer?
Direction: In the following questions, a statement of assertion is followed by a statement of reason. Mark the correct choice as:
Assertion : A light body and heavy body have same momentum. Then they also have same kinetic energy.
Reason : Kinetic energy depends on mass of the body.
a)
Both assertion and reason are true and reason is the correct explanation of assertion.
b)
Both assertion and reason are true but reason is not the correct explanation of assertion.
c)
Assertion is true but reason is false.
d)
Assertion is false but reason is true.
|
|
Dont Memorise answered |
Kinetic energy of a body of mass m1,
Again, kinetic energy of a body of mass m2,
If 
As given m2 > m1
Therefore, K1 > K2 i.e. the kinetic energy of light body will be more than the kinetic energy of heavy body when both have same momentum.
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:Assertion : Mitochondria are called ‘powerhouses’ of the cell.Reason : Mitochondria produce cellular energy in the form of ATP- a)Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
- b)Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
- c)Assertion (A) is true but reason (R) is false.
- d)Assertion (A) is false but reason (R) is true.
Correct answer is option 'A'. Can you explain this answer?
Direction: In the following questions, a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion : Mitochondria are called ‘powerhouses’ of the cell.
Reason : Mitochondria produce cellular energy in the form of ATP
a)
Both assertion (A) and reason (R) are true and reason (R) is the correct explanation of assertion (A).
b)
Both assertion (A) and reason (R) are true but reason (R) is not the correct explanation of assertion (A).
c)
Assertion (A) is true but reason (R) is false.
d)
Assertion (A) is false but reason (R) is true.
|
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Radha Iyer answered |
Mitochondria are cell organelles of aerobic eukaryotes. These are site of aerobic respiration, where Krebs cycle occurs in matrix, while ETS and oxidative phosphorylation enzymes are located in inner membrane. They are called powerhouses of cell because they produce energy in the form of ATP. They are the major centres of release of energy in the aerobic respiration.
Direction: Read the following and answer any four questions from (i) to (v).Manish and Nitish are provided with mixture of camphor, common salt and soil by their teacher. The teacher has asked them to use the techniques of sublimation, filtration and evaporation to separate this mixture.Q. Filtration technique can be used for separating ………. easily. - a)Camphor and soil
- b)Common salt and soil
- c)Camphor and common salt
- d)Camphor, common salt, soil
Correct answer is option 'B'. Can you explain this answer?
Direction: Read the following and answer any four questions from (i) to (v).
Manish and Nitish are provided with mixture of camphor, common salt and soil by their teacher. The teacher has asked them to use the techniques of sublimation, filtration and evaporation to separate this mixture.
Q. Filtration technique can be used for separating ………. easily.
a)
Camphor and soil
b)
Common salt and soil
c)
Camphor and common salt
d)
Camphor, common salt, soil
|
|
Swati Verma answered |
Filtration is a separation method used to separate out pure substances in mixtures comprised of particles some of which are large enough in size to be captured with a porous material. Particle size can vary considerably, given the type of mixture.
Direction: Read the following passage and answer the following questions.In order to overcome the objections raised against Rutherford’s model of the atom, Neil Bohr put forward the following postulates about the model of an atom.Q. Atoms are made up of ______, _____ and ______.- a)atomic number, mass number, nucleus
- b)Electrons, nucleus, shells
- c)Electrons, protons and neutrons
- d)None of these
Correct answer is option 'C'. Can you explain this answer?
Direction: Read the following passage and answer the following questions.
In order to overcome the objections raised against Rutherford’s model of the atom, Neil Bohr put forward the following postulates about the model of an atom.
Q. Atoms are made up of ______, _____ and ______.
a)
atomic number, mass number, nucleus
b)
Electrons, nucleus, shells
c)
Electrons, protons and neutrons
d)
None of these
|
|
Anita Menon answered |
Atoms are made up of fundamental particles and these fundamental particles are electrons, protons and neutrons.
Direction: Rahul took 5 moles of carbon atoms in a container and Sohan also took 5 moles of sodium atoms in another container of same weight.Q. Which container is heavier?- a)5 moles of carbon container
- b)5 moles of sodium container
- c)Both (a) and (b)
- d)None of these
Correct answer is option 'B'. Can you explain this answer?
Direction: Rahul took 5 moles of carbon atoms in a container and Sohan also took 5 moles of sodium atoms in another container of same weight.
Q. Which container is heavier?
a)
5 moles of carbon container
b)
5 moles of sodium container
c)
Both (a) and (b)
d)
None of these
|
|
Avinash Patel answered |
Mass of container containing 5 moles of C atoms = 5 × 12 = 60 g
Mass of container containing 5 moles of Na atoms = 5 x 23 = 115 g
Hence, container containing 5 moles of sodium is heavier.
Direction: All living Organisms are made up of cells and these cells perform all the functions essential for the survival of the Organism eg. respiration, digestion, excretion etc. In Unicellular organisms, a single cell carries out all these functions and in multicellular organisms different group of cells carry out different functions.Q. Select the Prokaryotic cell- a)Amoeba
- b)Bacteria
- c)Paramecium
- d)Hydra
Correct answer is option 'B'. Can you explain this answer?
Direction: All living Organisms are made up of cells and these cells perform all the functions essential for the survival of the Organism eg. respiration, digestion, excretion etc. In Unicellular organisms, a single cell carries out all these functions and in multicellular organisms different group of cells carry out different functions.
Q. Select the Prokaryotic cell
a)
Amoeba
b)
Bacteria
c)
Paramecium
d)
Hydra
|
|
Rohit Sharma answered |
Bacteria do not have a true nucleus or well developed nucleus. So, it is a Prokaryotic cell.
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Class 9: Additional Practice
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