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Which of the following is not matter?a)Blood b)Humidityc)Electrond)Moon rockCorrect answer is option 'B'. Can you explain this answer?
|
Samarth Goyal answered |
Not matter: Explanation
Introduction:
Matter is anything that has mass and takes up space. It is composed of atoms and molecules. However, there are some things that do not fall under the category of matter.
Non-Matter:
One of the following options is not matter:
- Blood: Blood is matter because it is composed of cells, plasma, and other substances that have mass and take up space.
- Humidity: Humidity is not matter because it is a measure of the amount of water vapor in the air. Water vapor is matter, but humidity is just a measurement.
- Electron: Electrons are matter because they are subatomic particles that have mass and take up space.
- Moon rock: Moon rock is matter because it is composed of minerals and other substances that have mass and take up space.
Conclusion:
Therefore, the correct answer is option B, humidity, as it is not matter.
Introduction:
Matter is anything that has mass and takes up space. It is composed of atoms and molecules. However, there are some things that do not fall under the category of matter.
Non-Matter:
One of the following options is not matter:
- Blood: Blood is matter because it is composed of cells, plasma, and other substances that have mass and take up space.
- Humidity: Humidity is not matter because it is a measure of the amount of water vapor in the air. Water vapor is matter, but humidity is just a measurement.
- Electron: Electrons are matter because they are subatomic particles that have mass and take up space.
- Moon rock: Moon rock is matter because it is composed of minerals and other substances that have mass and take up space.
Conclusion:
Therefore, the correct answer is option B, humidity, as it is not matter.
Capacity of doing work is called:- a)power
- b)momentum
- c)energy
- d)force.
Correct answer is option 'C'. Can you explain this answer?
Capacity of doing work is called:
a)
power
b)
momentum
c)
energy
d)
force.
|
Kavya Nambiar answered |
Energy and Work Energy is the capacity to do work or to produce heat. Internal energy is the sum of kinetic energy and the potential energy.
Cork cells are :-- a)Photosynthetic
- b)Elongated and participate in movement
- c)Meristematic
- d)Dead
Correct answer is option 'D'. Can you explain this answer?
Cork cells are :-
a)
Photosynthetic
b)
Elongated and participate in movement
c)
Meristematic
d)
Dead
|
Anita Menon answered |
Cork cells are dead with thick walls heavily impregnated with suberin.
Which one is not a plant fibre :-- a)Coir
- b)Flax
- c)Hemp
- d)Silk
Correct answer is option 'D'. Can you explain this answer?
Which one is not a plant fibre :-
a)
Coir
b)
Flax
c)
Hemp
d)
Silk
|
Sneha Jha answered |
Silk is animal fibre
Which of the following electron configuration represents a noble gas?- a)2, 8, 2
- b)2, 8, 6
- c)2, 8
- d)2, 8, 8, 2
Correct answer is option 'D'. Can you explain this answer?
Which of the following electron configuration represents a noble gas?
a)
2, 8, 2
b)
2, 8, 6
c)
2, 8
d)
2, 8, 8, 2
|
|
Arun Sharma answered |
Electronic configuration of noble gas atom can be identified by full Valence Electrons .
According to that of option C is correct of configuration 2,8.
According to that of option C is correct of configuration 2,8.
The radiant energy of sunlight is converted to chemical energy and stored as –- a)AMP
- b)ADP
- c)ATP
- d)APP
Correct answer is option 'C'. Can you explain this answer?
The radiant energy of sunlight is converted to chemical energy and stored as –
a)
AMP
b)
ADP
c)
ATP
d)
APP
|
Geetika Shah answered |
Sunlight is converted to chemical energy in the form of ATP (adenosine triphosphate), which is the main energy-storing molecule in living organisms. ATP is then transported throughout the chloroplast and used to provide the chemical energy necessary to power other metabolic reactions.
Which of the following has heighest kinetic energy?- a)Particles of ice at 0 °C
- b)Particles of water at 0 °C
- c)Particles of water at 100 °C
- d)Particles of steam at 100 °C
Correct answer is option 'D'. Can you explain this answer?
Which of the following has heighest kinetic energy?
a)
Particles of ice at 0 °C
b)
Particles of water at 0 °C
c)
Particles of water at 100 °C
d)
Particles of steam at 100 °C
|
|
Geetika Shah answered |
The particles of steam has highest kinetic energy because steam is in the form of gases in which the particles of gases are much apart from one another. The space between the particles of gases are very large. The force of attraction between the particles of gases is almost negligible. The particles of gases are free to move in any direction. When we heated the particles of gases it can move very rapidly. Hence, it's kinetic energy is maximum.
Can you explain the answer of this question below:A batsman hits a cricket ball, which then rolls on a level ground. After covering a short distance, the ball comes
to rest. The ball slows down to stop because:
- A:
the batsman did not hit the ball hard
- B:
velocity of ball is proportional to force acting on it
- C:
there is force on the ball opposing its motion
- D:
there is no unbalanced force on the ball and hence it comes to rest
The answer is C.
A batsman hits a cricket ball, which then rolls on a level ground. After covering a short distance, the ball comes
to rest. The ball slows down to stop because:
the batsman did not hit the ball hard
velocity of ball is proportional to force acting on it
there is force on the ball opposing its motion
there is no unbalanced force on the ball and hence it comes to rest
|
Hansa Sharma answered |
The cricket ball comes to rest after covering a short distance, because there is a force on the ball, opposing the motion. This force is due to resistance of air and also due to friction between the ball and the ground.
The animal which cannot hear ultrasonic waves is :- a)bat
- b)cow
- c)dog
- d)dolphin
Correct answer is option 'B'. Can you explain this answer?
The animal which cannot hear ultrasonic waves is :
a)
bat
b)
cow
c)
dog
d)
dolphin
|
Jyotsana answered |
Cow cannot hear ultra sound waves. As we know that ultrasound wave have higher frequencies than normal sound wave, but they also have shorter wavelengths. Humans cannot hear ultra sound same as Cow also cannot hear ultra sound waves because of frequency ranging between 20Hz to 20 KHz (20,000 Hz). Hence, Ultrasound cannot be hear by human as same as Cow also cannot hear ultra sound.
Organisms without nucleus and cell organelles belong to :
(i) Fungi (ii) Protista (iii) Cyanobacteria (iv) Archaebacteria- a)(A) (i) and (ii)
- b) (B) (iii) and (iv)
- c)(C) (i) and (iv)
- d)(D) (ii) and (iii)
Correct answer is option 'A'. Can you explain this answer?
Organisms without nucleus and cell organelles belong to :
(i) Fungi (ii) Protista (iii) Cyanobacteria (iv) Archaebacteria
(i) Fungi (ii) Protista (iii) Cyanobacteria (iv) Archaebacteria
a)
(A) (i) and (ii)
b)
(B) (iii) and (iv)
c)
(C) (i) and (iv)
d)
(D) (ii) and (iii)
|
|
Sarita Reddy answered |
Correct answer is b) (iii) and (iv):
Cyanobacteria and archaebacteria belong to kingdom-Monera. Monerans are organisms without nucleus and cell organelles and are called prokaryotes.
The barrier between the protoplasm and other environment in an animal cell is –
- a)Tonoplast
- b)Nuclear membrane
- c)Cell wall
- d)Plasma Membrane
Correct answer is option 'D'. Can you explain this answer?
The barrier between the protoplasm and other environment in an animal cell is –
a)
Tonoplast
b)
Nuclear membrane
c)
Cell wall
d)
Plasma Membrane
|
|
Sarita Reddy answered |
In animal cell it is plasma membrane, in plant cell it a a double barrier of plasma membrane and cell wall. Nuclear membrane is the barrier between nuclear material and other cell material. Tonoplast is the boundary/outer wall of a vacuole.
The force of freely falling body is directly proportional to:- a)mass of body
- b)acceleration of body
- c)velocity of body
- d)both (A) and (B)
Correct answer is option 'D'. Can you explain this answer?
The force of freely falling body is directly proportional to:
a)
mass of body
b)
acceleration of body
c)
velocity of body
d)
both (A) and (B)
|
|
Arvind Singh answered |
The acceleration of an object is directly proportional to the net force acting on the object and inversely proportional to the object's mass.
Animal cell is limited by–- a)Plasma membrane
- b)Shell membrane
- c)Cell wall
- d)Basement membrane
Correct answer is option 'A'. Can you explain this answer?
Animal cell is limited by–
a)
Plasma membrane
b)
Shell membrane
c)
Cell wall
d)
Basement membrane
|
Prachi Rathore answered |
Yes, it is true that cells of animals are limited by plasma membrane because it is the outermost covering of animal cell and cell's shape and size depends on that plasma membrane.
What is the weight of 3 gram atoms of sulphur ?
- a)98 g
- b)99 g
- c)95 g
- d)96 g
Correct answer is option 'D'. Can you explain this answer?
What is the weight of 3 gram atoms of sulphur ?
a)
98 g
b)
99 g
c)
95 g
d)
96 g
|
|
Ananya Das answered |
Weight of atom = atomic mass × Given mass
⇒ 3g × 32g
= 96 g
weight of 3 grams of atoms of sulphur is 96 g.
Bohr's atomic theory gave the idea of :-- a)Quantum numbers
- b)Shape of sublevels
- c)Nucleus
- d)Stationary states
Correct answer is option 'D'. Can you explain this answer?
Bohr's atomic theory gave the idea of :-
a)
Quantum numbers
b)
Shape of sublevels
c)
Nucleus
d)
Stationary states
|
Kanta Jindal answered |
Bohr's atomic theory says that each shell has its own energy and it neither loses nor gains energy and due to this atoms are static and therefore this energy shells are called stationary states
The growth in plants is :-- a)Cuased by each and every cell of the body
- b)Limited to certain regions
- c)Caused by non-dividing regions
- d)Uniform
Correct answer is option 'B'. Can you explain this answer?
The growth in plants is :-
a)
Cuased by each and every cell of the body
b)
Limited to certain regions
c)
Caused by non-dividing regions
d)
Uniform
|
|
Anita Menon answered |
The reason for this is the presence of meristematic cells which are present only in some regions in the plant.
Meristematic tissues are cells or group of cells that have the ability to divide. These tissues in a plant consist of small, densely packed cells that can keep dividing to form new cells.
Meristematic tissues is found in the followinglocations:
near tips of roots and stems. This is called apical meristems.
in the buds and nodes of stems.
in the cambium between the xylem and phloem in dicotyledonous trees and shrubs.
under the epidermis of dicotyledonous trees and shrubs (cork cambium).
in the pericycle of roots, producing branch roots.
Two bodies collide at the same time. Which of the following is conserved?- a)velocity
- b)momentum
- c)kinetic energy
- d)force
Correct answer is option 'C'. Can you explain this answer?
Two bodies collide at the same time. Which of the following is conserved?
a)
velocity
b)
momentum
c)
kinetic energy
d)
force
|
|
Arjun Sharma answered |
In a inelastic collision only momentum is conserved. Kinetic energy is not conserved Loss of heat may takes place so temperature is not conserved. Since Kinetic energy is not conserved, velocity is not conserved.
A boy sitting in a boat fires a gun. An observer P is at a distance of 50 m from the boat. Another observerQ is a diver, who is 50 m under water. Both hear the sound of gun:- a)P hears the sound first
- b)Q hears the sound first
- c)Both P and Q hear the sound at the same time
- d)none of the above.
Correct answer is option 'B'. Can you explain this answer?
A boy sitting in a boat fires a gun. An observer P is at a distance of 50 m from the boat. Another observer
Q is a diver, who is 50 m under water. Both hear the sound of gun:
a)
P hears the sound first
b)
Q hears the sound first
c)
Both P and Q hear the sound at the same time
d)
none of the above.
|
|
Ria Shah answered |
Explanation:
When a gun is fired, it produces a sound wave that spreads out in all directions. This sound wave travels through the air and water at different speeds, which means that the time taken for the sound to reach an observer on land and an observer underwater will be different.
Observer P hears the sound first:
If the sound travels faster through air than through water, then observer P will hear the sound first. This is because the sound wave will reach them before it reaches observer Q, who is underwater. However, this is not the case as sound travels faster through water than air.
Both P and Q hear the sound at the same time:
If the sound travels at the same speed through air and water, then both observers will hear the sound at the same time. This is because the sound wave will travel through both mediums at the same speed. However, this is also not the case as sound travels faster through water than air.
Observer Q hears the sound first:
As sound travels faster through water than air, observer Q, who is underwater, will hear the sound first. This is because the sound wave will travel through water and reach Q before it reaches P on land. Therefore, the correct answer is option 'B' - Q hears the sound first.
Conclusion:
The speed of sound is different in different mediums. When the sound wave travels through air and water, it travels at different speeds, which means that the time taken for the sound to reach observers on land and underwater will be different. In this case, as sound travels faster through water than air, observer Q, who is underwater, will hear the sound first.
When a gun is fired, it produces a sound wave that spreads out in all directions. This sound wave travels through the air and water at different speeds, which means that the time taken for the sound to reach an observer on land and an observer underwater will be different.
Observer P hears the sound first:
If the sound travels faster through air than through water, then observer P will hear the sound first. This is because the sound wave will reach them before it reaches observer Q, who is underwater. However, this is not the case as sound travels faster through water than air.
Both P and Q hear the sound at the same time:
If the sound travels at the same speed through air and water, then both observers will hear the sound at the same time. This is because the sound wave will travel through both mediums at the same speed. However, this is also not the case as sound travels faster through water than air.
Observer Q hears the sound first:
As sound travels faster through water than air, observer Q, who is underwater, will hear the sound first. This is because the sound wave will travel through water and reach Q before it reaches P on land. Therefore, the correct answer is option 'B' - Q hears the sound first.
Conclusion:
The speed of sound is different in different mediums. When the sound wave travels through air and water, it travels at different speeds, which means that the time taken for the sound to reach observers on land and underwater will be different. In this case, as sound travels faster through water than air, observer Q, who is underwater, will hear the sound first.
A hydrogen contain 90% of carbon and 10% hydrogen. The empirical formula of the compound is :-- a)C2H5
- b)C3H2
- c)C3H4
- d)C H3
Correct answer is option 'C'. Can you explain this answer?
A hydrogen contain 90% of carbon and 10% hydrogen. The empirical formula of the compound is :-
a)
C2H5
b)
C3H2
c)
C3H4
d)
C H3
|
Jyoti Kapoor answered |
Given C 90%, H10%.
So Moles of element C = 90/12 =7.5
So Moles of element H = 10/1 =10
Simplest molar ration of carbon= 7.5/7.5=1
Simplest molar ration of H= 10/7.5=1.33
whole no ratio element C= 1*3=3
whole no ratio element H= 1.33*3=4
so its C3H4
Which of the following would not be considered part of a cell's cytoplsm?- a)Ribosome
- b)Nucleus
- c)Mitochondrion
- d)Microtubule
Correct answer is option 'B'. Can you explain this answer?
Which of the following would not be considered part of a cell's cytoplsm?
a)
Ribosome
b)
Nucleus
c)
Mitochondrion
d)
Microtubule
|
Pooja Shah answered |
Nucleoplasm has a little different composition. Nucleoplasm can only be found inside of the nucleus. It doesn't have big organelles in suspension. The nucleoplasm is the suspension fluid that holds the cell's chromatin and nucleolus. It is not always present in the nucleus. When the cell divides, the nuclear membrane dissolves and the nucleoplasm is released. After the cell nucleus has reformed, the nucleoplasm fills the space again.
When water particles condenses on air on dust, it forms :-- a)Mist
- b)Fog
- c)Frost
- d)Vapour
Correct answer is option 'A'. Can you explain this answer?
When water particles condenses on air on dust, it forms :-
a)
Mist
b)
Fog
c)
Frost
d)
Vapour
|
|
Arvind Singh answered |
Mist
- The difference between the mist and fog is that mist contains more moisture than fog.
- In mist each nuclei contains a thicker layer of moisture.
- Mists are frequent over mountains as the rising warm air up the slopes meets a cold surface.
- Mist is also formed by water droplets, but with less merging or coalescing. This means mist is less dense and quicker to dissipate.
- Fogs are drier than mist and they are prevalent where warm currents of air come in contact with cold currents.
- In mist visibility is more than one kilometer but less than two kilometres.
Growing different crops in the same field in a preplanned succession is :-- a)Crop management
- b)Crop rotation
- c)Intercropping
- d)Plant breeding
Correct answer is option 'B'. Can you explain this answer?
Growing different crops in the same field in a preplanned succession is :-
a)
Crop management
b)
Crop rotation
c)
Intercropping
d)
Plant breeding
|
|
Arvind Singh answered |
Crop rotation is the systematic planting of different crops in a particular order over several years in the same growing space. This process helps maintain nutrients in the soil, reduce soil erosion, and prevents plant diseases and pests.
There is no universally accepted rotation schedule as the types of plants in a particular farm or garden depend on the local soil, climate, and resources available. The length of rotation time between different plants will also vary depending on the needs of the gardener.
Which of the following does not affect rate of evaporation? - a) Wind speed
- b) Surface area
- c) Temperature
- d) Insoluble heavy impurities
Correct answer is option 'D'. Can you explain this answer?
Which of the following does not affect rate of evaporation?
a)
Wind speed
b)
Surface area
c)
Temperature
d)
Insoluble heavy impurities
|
|
Ananya Das answered |
Adding salt to water results in a phenomenon called boiling point elevation.
NaCl readily dissolves in water, but unlike water molecules, trying to move dissolved sodium or chlorine ions into the vapour phase requires very large amounts of energy. The boiling point of (pure) water is 100 degree C and at this temperature, the dissolved ions simply remain in solution.
The effect is quite small. Dissolving 60 g of salt in a litre of water only raises the boiling point from 100.0 deg C to 100.5 deg C.
In the kinetic theory of gases, it is assumed that molecular collisions are :-a) elasticb)Short in durationc)One-dimensionald)Not able to exert mutual forcesCorrect answer is option 'B'. Can you explain this answer?
|
|
Hansa Sharma answered |
The model, called the kinetic theory of gases, assumes that the molecules are very small relative to the distance between molecules. The molecules are in constant, random motion and frequently collide with each other and with the walls of any container.
Practice Test/Quiz or MCQ (Multiple Choice Questions) with Solutions of Chapter "Plant Tissues (Tissues)" are available for CBSE Class 9 Science and have been compiled as per the syllabus of CBSE Class 9 ScienceQ. Prosenchyma is a type of :-- a)Chlorenchyma
- b)Collenchyma
- c)Parenchyma
- d)Sclerenchyma
Correct answer is option 'C'. Can you explain this answer?
Practice Test/Quiz or MCQ (Multiple Choice Questions) with Solutions of Chapter "Plant Tissues (Tissues)" are available for CBSE Class 9 Science and have been compiled as per the syllabus of CBSE Class 9 Science
Q. Prosenchyma is a type of :-
a)
Chlorenchyma
b)
Collenchyma
c)
Parenchyma
d)
Sclerenchyma
|
Jiya Kumari answered |
Hey, Prosenchyma is a type of (c) Parenchyma. Prosenchyma is a type of parenchyma where cells are elongated with tapering ends. In some cases the cells are long and taper at either ends (as in pericycle of some plants). This is called a prosenchyma This tissue has manifold functions (i) It performs physiological functions like photosynthesis, secretion, assimilation and storages. (ii) Aerenchyma provides buoyancy to hydrophytes and also helps in gaseous exchange. (iii) It helps in healing of wound and regeneration of organs. (iv) Prosenchyma provides strength and helps in conduction. (v) It helps in formation of adventitious roots and buds. HOPE IT HELPS YOU.
Which one of the following is the indigenous breed of chickens :-- a)Plymouth rock
- b)White leghorn
- c)Aseel
- d)Rhode island red
Correct answer is option 'C'. Can you explain this answer?
Which one of the following is the indigenous breed of chickens :-
a)
Plymouth rock
b)
White leghorn
c)
Aseel
d)
Rhode island red
|
|
Geetika Shah answered |
Aseel is an important native chicken breed of India, known for its martial qualities (aggressive fighting abilities), pugnacity, and majestic gait. The aim of the study is to conserve and characterize the Aseel germplasm, which is considered to be endangered.
A body of mass 20 kg, slows down from 5 ms-1 to 2 ms-1 by a retarding force. The work done by the force is:- a)–50J
- b)–200J
- c)–300J
- d)–210J
Correct answer is option 'B'. Can you explain this answer?
A body of mass 20 kg, slows down from 5 ms-1 to 2 ms-1 by a retarding force. The work done by the force is:
a)
–50J
b)
–200J
c)
–300J
d)
–210J
|
Preetam Pyare answered |
W=kinetic energy possessed. .
=[(1/2) (m) (v^2)] - [(1/2 ) (m) (u^2)]...
=(1/2) (m) [(v^2)-(u^2)]...
=(1/2) (20) [(2×2)-(5×5)]..
=(10) (-21)...
=(-210)J . ...
Double membrane is absent in –- a)Mitochondrion
- b)Chloroplast
- c)Nucleus
- d)Lysosome
Correct answer is 'D'. Can you explain this answer?
Double membrane is absent in –
a)
Mitochondrion
b)
Chloroplast
c)
Nucleus
d)
Lysosome
|
|
Sarita Reddy answered |
Because, plastid nucleus and mitochondria are the three organelles which are double membrane bound
Which of the following electronic configuration is wrong ?- a)Be (3) = 2, 1
- b)O (8) = 2, 6
- c)S (16) = 2, 6, 8
- d)P (15) = 2, 8, 5
Correct answer is option 'B'. Can you explain this answer?
Which of the following electronic configuration is wrong ?
a)
Be (3) = 2, 1
b)
O (8) = 2, 6
c)
S (16) = 2, 6, 8
d)
P (15) = 2, 8, 5
|
Mishti Gupta answered |
Electronic Configuration of Atoms
Electronic configuration refers to the arrangement of electrons in the shells/orbitals of an atom. The electronic configuration of an atom determines its chemical properties and its reactivity with other atoms.
Explanation of Options
a) Be (3) = 2, 1
The electronic configuration of beryllium (Be) is 1s2 2s2. The atomic number of beryllium is 4, which means that it has 4 electrons. The electronic configuration mentioned in option (a) is correct.
b) O (8) = 2, 6
The electronic configuration of oxygen (O) is 1s2 2s2 2p4. The atomic number of oxygen is 8, which means that it has 8 electrons. The electronic configuration mentioned in option (b) is incorrect. It should be 1s2 2s2 2p6.
c) S (16) = 2, 6, 8
The electronic configuration of sulfur (S) is 1s2 2s2 2p6 3s2 3p4. The atomic number of sulfur is 16, which means that it has 16 electrons. The electronic configuration mentioned in option (c) is correct.
d) P (15) = 2, 8, 5
The electronic configuration of phosphorus (P) is 1s2 2s2 2p6 3s2 3p3. The atomic number of phosphorus is 15, which means that it has 15 electrons. The electronic configuration mentioned in option (d) is correct.
Conclusion
In conclusion, the correct answer is option (b) O (8) = 2, 6 because the electronic configuration should be 1s2 2s2 2p6 and not 2, 6.
Electronic configuration refers to the arrangement of electrons in the shells/orbitals of an atom. The electronic configuration of an atom determines its chemical properties and its reactivity with other atoms.
Explanation of Options
a) Be (3) = 2, 1
The electronic configuration of beryllium (Be) is 1s2 2s2. The atomic number of beryllium is 4, which means that it has 4 electrons. The electronic configuration mentioned in option (a) is correct.
b) O (8) = 2, 6
The electronic configuration of oxygen (O) is 1s2 2s2 2p4. The atomic number of oxygen is 8, which means that it has 8 electrons. The electronic configuration mentioned in option (b) is incorrect. It should be 1s2 2s2 2p6.
c) S (16) = 2, 6, 8
The electronic configuration of sulfur (S) is 1s2 2s2 2p6 3s2 3p4. The atomic number of sulfur is 16, which means that it has 16 electrons. The electronic configuration mentioned in option (c) is correct.
d) P (15) = 2, 8, 5
The electronic configuration of phosphorus (P) is 1s2 2s2 2p6 3s2 3p3. The atomic number of phosphorus is 15, which means that it has 15 electrons. The electronic configuration mentioned in option (d) is correct.
Conclusion
In conclusion, the correct answer is option (b) O (8) = 2, 6 because the electronic configuration should be 1s2 2s2 2p6 and not 2, 6.
Calculate the number of gram atoms present in 8g of helium- a)3
- b)4
- c)2
- d)1
Correct answer is option 'A'. Can you explain this answer?
Calculate the number of gram atoms present in 8g of helium
a)
3
b)
4
c)
2
d)
1
|
|
Arjun Sharma answered |
Atomic mass of Helium is 4. So if you take 4 grams of Helium atom,then the number of atoms in it will be 6.0203x10^23,that is avogadro number. If you take 8 grams of Helium,then it will be double of avogadro number. Ans: 2x6.023x10^23
Latent heat of fusion for ice is :-- a)80 gm cal-1
- b)80 cal / gm
- c)19 J cal-1
- d)None of these
Correct answer is option 'B'. Can you explain this answer?
Latent heat of fusion for ice is :-
a)
80 gm cal-1
b)
80 cal / gm
c)
19 J cal-1
d)
None of these
|
|
Ananya Das answered |
The latent heat of vaporization of water is 540 cal/g/°C and the latent heat of fusion of ice is 80 cal/g/°C. At higher pressures, it takes more than 540 calories for every gram to vaporize.
Valency of iron in FeCl2 and FeCl3 is _______ and _______ respectively- a)1, 2
- b)2, 1
- c)2, 3
- d)3, 2
Correct answer is option 'B'. Can you explain this answer?
Valency of iron in FeCl2 and FeCl3 is _______ and _______ respectively
a)
1, 2
b)
2, 1
c)
2, 3
d)
3, 2
|
Anam Naaz answered |
Fecl2 = valency of fe = 2 Fecl3 = valency of fe = 3 hence, it should be C?
If the nucleus is a cell's "control centre" and chloroplasts its "solar collectors". Which of the following might be called the cell's combination "food processor" and "garbage disposer"?- a)Lysosome
- b)Ribosome
- c)Golgi apparatus
- d)Nucleolus
Correct answer is option 'A'. Can you explain this answer?
If the nucleus is a cell's "control centre" and chloroplasts its "solar collectors". Which of the following might be called the cell's combination "food processor" and "garbage disposer"?
a)
Lysosome
b)
Ribosome
c)
Golgi apparatus
d)
Nucleolus
|
Vikram Khanna answered |
One of the key organelles involved in digestion and waste removal is the lysosome. Lysosomes are organelles that contain digestive enzymes. They digest excess or worn out organelles, food particles, and engulfed viruses or bacteria.
A satellite which is geostationary in a particular orbit is taken to another orbit. Its distance from the centreof earth in new orbit is 2 times than that of the earlier orbit. The time period in the second orbit is- a)4.8 hours
- b)48√2 hours
- c)24 hours
- d)24√2 hours
Correct answer is option 'D'. Can you explain this answer?
A satellite which is geostationary in a particular orbit is taken to another orbit. Its distance from the centre
of earth in new orbit is 2 times than that of the earlier orbit. The time period in the second orbit is
a)
4.8 hours
b)
48√2 hours
c)
24 hours
d)
24√2 hours
|
|
Sarita Reddy answered |
The answer is b.
T∝r^3/2. If r becomes double then time period will becomes (2)3/2 times. So new time period will be
T∝r^3/2. If r becomes double then time period will becomes (2)3/2 times. So new time period will be
Kingdom protista includes :-
- a)Life cycle showing sporic meiosis
- b)Life cycle showing zygotic meiosis
- c)Both B and D
- d)Life cycle showing gametic meiosis
Correct answer is option 'C'. Can you explain this answer?
Kingdom protista includes :-
a)
Life cycle showing sporic meiosis
b)
Life cycle showing zygotic meiosis
c)
Both B and D
d)
Life cycle showing gametic meiosis
|
|
Ananya Sharma answered |
Life cycle showing gametic meiosis
Organism spends most of its life time in 2n condition.
Gametes are n type and produced by meiosis.
Gametes fuse to form zygote and grows into a diploid organism.
Gymnosperms do not have :-
- a)Ovule
- b)Antheridium
- c)Archegonium
- d)Egg
Correct answer is option 'B'. Can you explain this answer?
Gymnosperms do not have :-
a)
Ovule
b)
Antheridium
c)
Archegonium
d)
Egg
|
Mira Sharma answered |
Gymnosperms do not have:
- Antheridium: Antheridium is the male reproductive structure found in bryophytes and pteridophytes, but not in gymnosperms. Gymnosperms have male cones that produce pollen grains.
- Archegonium: Archegonium is the female reproductive structure found in bryophytes and pteridophytes, but not in gymnosperms. Gymnosperms have female cones that contain ovules.
- Ovule: Ovules are the structures that contain the female gametophyte and eventually develop into seeds after fertilization. Gymnosperms have ovules that are exposed on the surface of the cones, unlike angiosperms where ovules are enclosed within the ovary.
- Egg: Eggs are the female gametes that are fertilized by the male gametes to form a zygote. Gymnosperms have eggs, but they are not produced within archegonia like in bryophytes and pteridophytes.
In summary, gymnosperms lack antheridia, archegonia, and enclosed ovules, although they do have eggs.
- Antheridium: Antheridium is the male reproductive structure found in bryophytes and pteridophytes, but not in gymnosperms. Gymnosperms have male cones that produce pollen grains.
- Archegonium: Archegonium is the female reproductive structure found in bryophytes and pteridophytes, but not in gymnosperms. Gymnosperms have female cones that contain ovules.
- Ovule: Ovules are the structures that contain the female gametophyte and eventually develop into seeds after fertilization. Gymnosperms have ovules that are exposed on the surface of the cones, unlike angiosperms where ovules are enclosed within the ovary.
- Egg: Eggs are the female gametes that are fertilized by the male gametes to form a zygote. Gymnosperms have eggs, but they are not produced within archegonia like in bryophytes and pteridophytes.
In summary, gymnosperms lack antheridia, archegonia, and enclosed ovules, although they do have eggs.
Milk is a _______ solution while vinegar is a ________ solution.a)Suspension, colloidalb)Colloidal, suspensionc)True, colloidald)Colloidal, trueCorrect answer is option 'D'. Can you explain this answer?
|
Ravi Verma answered |
True Solution: True Solution is a homogeneous mixture of two or more substances in which substance dissolved (solute) in solvent has the particle size of less than 10-9 m or 1 nm. Simple solution of sugar in water is an example of true solution.
True solutions example: vinegar
Colloidal: a homogeneous non-crystalline substance consisting of large molecules or ultramicroscopic particles of one substance dispersed through a second substance. Colloids include gels, sols, and emulsions; the particles do not settle, and cannot be separated out by ordinary filtering or centrifuging like those in a suspension.
Colloids example: Milk
For the motion on a straight line path with constant acceleration the ratio of the magnitude of thedisplacement to the distance covered is :-- a)= 1
- b)
- c)
- d)< 1
Correct answer is option 'A'. Can you explain this answer?
For the motion on a straight line path with constant acceleration the ratio of the magnitude of thedisplacement to the distance covered is :-
a)
= 1
b)
c)
d)
< 1
|
|
Abhishek Dubey answered |
The magnitude of distance travelled in a given time interval is always greater than or equal to the displacement. It can never be less than the displacement.
The ratio of the displacement to the distance is equal to or less than one (≤1).
The ratio of the displacement to the distance is equal to or less than one (≤1).
Based on the statements given here choose the correct answer.
(1) Some sugar can be added to a full glass of water without causing overflow.
(2) Liquid have spaces present between the molecules.
- a)(1) and (2) are true and (2) explains (1)
- b)(1) and (2) are true but (2) does not explain (1)
- c)Only (1) is true
- d)Only (2) is true
Correct answer is option 'A'. Can you explain this answer?
Based on the statements given here choose the correct answer.
(1) Some sugar can be added to a full glass of water without causing overflow.
(2) Liquid have spaces present between the molecules.
(1) Some sugar can be added to a full glass of water without causing overflow.
(2) Liquid have spaces present between the molecules.
a)
(1) and (2) are true and (2) explains (1)
b)
(1) and (2) are true but (2) does not explain (1)
c)
Only (1) is true
d)
Only (2) is true
|
Learning Enablers answered |
The liquid is a substance with indefinite shape. They have weak intermolecular space so they are not closely packed, So they have spaces between the molecules. When sugar is added, the glucose molecules occupy these spaces and do not cause an overflow.
Hence, 1 and 2 are true and 2 correctly explains 1.
A stone weighing 3 kg falls from the top of a tower 100 m high and buries itself 2 m deepin the sand. The time of penetration is :-- a)0.09 sec
- b)0.9 sec
- c)2.1 sec
- d)1.3 sec
Correct answer is 'A'. Can you explain this answer?
A stone weighing 3 kg falls from the top of a tower 100 m high and buries itself 2 m deepin the sand. The time of penetration is :-
a)
0.09 sec
b)
0.9 sec
c)
2.1 sec
d)
1.3 sec
|
Divya Ahuja answered |
Given:-
m= 3 kg
u= 0
h= 100 m
g= 9.8 m/s^2
Using 3rd equation of motion:-
v^2-u^2= 2 gh
v^2 - 0^2= 2 (9.8) 100
v= 2√490
v= 14√10 m/s
Now, during penetration:-
u= 14√10 m/s
v= 0
S= 2 m
a= ?
t= ?
Using 3rd equation of motion:-
v^2-u^2= 2 aS
0^2 - (14√10)^2= (2) a (2)
4a= -1960
a= -490 m/s^2
Now, using 1st equation is motion:-
v= u+at
0= 14√10 + (-490)t
t= 14√10/490
t= 0.0903 sec
Hence the correct alternative is (a) 0.09 sec
The principle of conservation of linear momentum states that in a system it :- a)cannot be changed
- b)can be changed, if internal forces act on it
- c)can be changed, if external forces act on it
- d)none of the above
Correct answer is option 'A'. Can you explain this answer?
The principle of conservation of linear momentum states that in a system it :
a)
cannot be changed
b)
can be changed, if internal forces act on it
c)
can be changed, if external forces act on it
d)
none of the above
|
|
Jyoti Kapoor answered |
Law of Conservation of Momentum
In general, the law of conservation of momentum or principle of momentum conservation states that the momentum of an isolated system is a constant. The vector sum of the momenta (momentum is equal to the mass of an object multiplied by its velocity) of all the objects of a system cannot be changed by interactions within the system. In classical mechanics, this law is implied by Newton’s laws. This principle is a direct consequence of Newton’s third law.
Which one is a micronutrient :-- a)Iron
- b)Calcium
- c)Magnesium
- d)Potassium
Correct answer is option 'A'. Can you explain this answer?
Which one is a micronutrient :-
a)
Iron
b)
Calcium
c)
Magnesium
d)
Potassium
|
|
Dharmender Sharma answered |
Iron is an important micronutrient that ensures the development of normal red blood cells and healthy immune function. Iron deficiency is the most common and widespread nutritional deficiency in the world – affecting the very poor, especially women – and is the cause of about half of all cases of anaemia.
Liquid dispersed in gas is called :- a)Aerosol
- b)Solid sol
- c)Sol
- d)Solid foam
Correct answer is option 'A'. Can you explain this answer?
Liquid dispersed in gas is called :
a)
Aerosol
b)
Solid sol
c)
Sol
d)
Solid foam
|
Shivam Patel answered |
Aerosol: Liquid Dispersed in Gas
Aerosol is a term used to describe a system where a liquid is dispersed in a gas. This type of system is commonly found in sprays, where a liquid substance is forced through a nozzle and dispersed into the surrounding air. The resulting mist or fog is made up of tiny droplets of the liquid that are suspended in the gas.
Properties of Aerosols
Aerosols can have a variety of properties depending on the type of liquid and gas involved. Some common properties of aerosols include:
- Particle size: The size of the droplets in an aerosol can vary widely, from nanometers to millimeters. This can affect the behavior of the aerosol, such as how it disperses or settles.
- Concentration: The concentration of the liquid in the gas can also vary, from very low levels to highly concentrated clouds of droplets.
- Stability: Some aerosols are stable and will remain suspended in the gas for a long time, while others will quickly settle out or evaporate.
- Behavior: Aerosols can exhibit a range of behaviors, from simple diffusion to complex interactions with surfaces or other aerosols.
Applications of Aerosols
Aerosols have a wide range of practical applications, including:
- Sprays: Aerosol sprays are used in a variety of consumer products, such as perfumes, deodorants, cleaning products, and insecticides.
- Medical treatments: Aerosols can be used to deliver medications directly to the lungs or other parts of the body.
- Industrial processes: Aerosols can be used in industrial applications such as painting, coating, and lubrication.
- Environmental monitoring: Aerosols can be used to study air quality and pollution levels.
In conclusion, aerosol is a term used to describe a system where a liquid is dispersed in a gas. It has a wide range of properties and applications, making it an important area of study in various fields.
Aerosol is a term used to describe a system where a liquid is dispersed in a gas. This type of system is commonly found in sprays, where a liquid substance is forced through a nozzle and dispersed into the surrounding air. The resulting mist or fog is made up of tiny droplets of the liquid that are suspended in the gas.
Properties of Aerosols
Aerosols can have a variety of properties depending on the type of liquid and gas involved. Some common properties of aerosols include:
- Particle size: The size of the droplets in an aerosol can vary widely, from nanometers to millimeters. This can affect the behavior of the aerosol, such as how it disperses or settles.
- Concentration: The concentration of the liquid in the gas can also vary, from very low levels to highly concentrated clouds of droplets.
- Stability: Some aerosols are stable and will remain suspended in the gas for a long time, while others will quickly settle out or evaporate.
- Behavior: Aerosols can exhibit a range of behaviors, from simple diffusion to complex interactions with surfaces or other aerosols.
Applications of Aerosols
Aerosols have a wide range of practical applications, including:
- Sprays: Aerosol sprays are used in a variety of consumer products, such as perfumes, deodorants, cleaning products, and insecticides.
- Medical treatments: Aerosols can be used to deliver medications directly to the lungs or other parts of the body.
- Industrial processes: Aerosols can be used in industrial applications such as painting, coating, and lubrication.
- Environmental monitoring: Aerosols can be used to study air quality and pollution levels.
In conclusion, aerosol is a term used to describe a system where a liquid is dispersed in a gas. It has a wide range of properties and applications, making it an important area of study in various fields.
The SI unit of temperature is :-a)°Cb)Kc)°Fd)All of the aboveCorrect answer is 'B'. Can you explain this answer?
|
|
Arun Sharma answered |
Kelvin is the SI unit of Temperature. Kelvin (K) is the fraction 1/273.16 of the thermodynamic temperature of the triple point of water. The temperature 0 K is commonly referred to as "absolute zero."
Valency of tin in SO2 and SO3 is _______ and _______ respectively- a)3, 6
- b)2, 3
- c)2, 6
- d)4, 6
Correct answer is option 'D'. Can you explain this answer?
Valency of tin in SO2 and SO3 is _______ and _______ respectively
a)
3, 6
b)
2, 3
c)
2, 6
d)
4, 6
|
Jyothi Biju answered |
The 2oxygen atom have 4together And because so2 has no charge if it then the total charge shape of which leads to the charge of so2
A bullet of mass 0.01 kg is fired from a rifle. The bullet takes 0.003 s to move through the barrel and leaves with a velocity of 300 ms–1. The acceleration acting on the bullet is :- a)10,000 ms–2
- b)100,000 ms–2
- c)1000,000 ms–2
- d)1000 ms–2
Correct answer is option 'B'. Can you explain this answer?
A bullet of mass 0.01 kg is fired from a rifle. The bullet takes 0.003 s to move through the barrel and leaves with a velocity of 300 ms–1. The acceleration acting on the bullet is :
a)
10,000 ms–2
b)
100,000 ms–2
c)
1000,000 ms–2
d)
1000 ms–2
|
|
Ravi Verma answered |
GIVEN,
MASS OF BULLET(m) = 10G = 10/1000 = 0.01KG
TIME TAKEN(t) = 0.003 SECS.
INITIAL VELOCITY (u) =300 M/S
FINAL VELOCITY (v) = 0.
ACCELERATION (a) =?
FORCE (F) = ?
BY USING 1ST EQUATION OF MOTION,
WE GET,
v = u + at
300 = 0 + a X 0.003
300 = a X 0.003
300/0.003 = a
100,000 = a
OR
a = 100,000 M/S2.
NOW,
WE KNOW THAT,
F = m X a
= 0.01 X 100,000
= 1000 N..
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