All India NEET Group

A male human is heterozygous for autosomal genes A and B and is also hemizygous for haemophilic gene h. What proportion of his sperms will be abh?
  • a)
    1/8
  • b)
    1/32
  • c)
    1/16
  • d)
    1/4
Correct answer is option 'A'. Can you explain this answer?

Rajesh Dasgupta answered  •  9 minutes ago
Calculation of Proportion of ABH Sperms
To determine the proportion of ABH sperms produced by the male individual, we need to consider the genetic makeup of the individual.

Heterozygous for Autosomal Genes A and B
The individual is heterozygous for autosomal genes A and B. This means that he has two different alleles for each gene. As a result, he can produce fo
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What is the difference between ex situ and in situ conservation?

Advait Das answered  •  48 minutes ago
Ex Situ vs In Situ Conservation
Ex Situ Conservation:
- Ex situ conservation involves the preservation of species outside their natural habitat.
- This method is often used when species are facing immediate threats in their natural environment.
- Examples of ex situ conservation include zoos, botanical gardens, seed banks, and captive breeding programs.
- It allows for the
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please send me important trigonometry formulas essential for neet

Advait Das answered  •  58 minutes ago
Trigonometry Formulas for NEET

1. Pythagorean Identities:
- $\sin^2 x + \cos^2 x = 1$
- $1 + \tan^2 x = \sec^2 x$
- $1 + \cot^2 x = \csc^2 x$

2. Angle Addition and Subtraction Formulas:
- $\sin(A \pm B) = \sin A \cos B \pm \cos A \sin B$
- $\cos(A \pm B) = \cos A \cos B \mp \sin A \sin B$
- $\tan(A \pm B) = \frac{\tan A \pm \
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A satellite in force free space sweeps stationary interplanetary dust at a rate dM/dt = αv where M is the mass and v is the velocity of the satellite and α is a constant. What is the deceleration of the satellite? [1994]
  • a)
    -αv2
  • b)
    -αv2/2M
  • c)
    -αv2/M
  • d)
    -2αv2/M
Correct answer is option 'C'. Can you explain this answer?

Nilanjan Kapoor answered  •  5 hours ago
Deceleration of the Satellite:
- Given: dM/dt = αv, where M is the mass and v is the velocity of the satellite, and α is a constant.
- The force acting on the satellite is equal to the rate of change of momentum.
- The force is given by F = dp/dt = d(Mv)/dt
- Using the product rule, we get F = v dM/dt + M dv/dt
- Substituting dM/dt = αv, we
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The mean radius of earth is R, its angular speed on its own axis is ω and the acceleration due to gravity at earth's surface is g. What will be the radius of the orbit of a geostationary satellite ? [1992]
  • a)
    ( R2g/ω2)1/3
  • b)
    ( Rg/ω2)1/3
  • c)
    ( R2ω2/g)1/3
  • d)
    ( R 2g /ω)1/3
Correct answer is option 'A'. Can you explain this answer?

Advait Joshi answered  •  5 hours ago
Concept:
The radius of the orbit of a geostationary satellite can be calculated using the formula for centripetal force in a circular motion.

Given:
Mean radius of Earth = R
Angular speed on its own axis = ω
Acceleration due to gravity at Earth's surface = g

Formula:
For a geostationary satellite, the centripetal force required fo
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A satellite of mass m is orbiting around the earth in a circular orbit with a velocity v. What will be its total energy? [1991]
  • a)
    (3/4) mv2
  • b)
    (1/2) mv2
  • c)
    mv2
  • d)
    – (1/2)m v2
Correct answer is option 'D'. Can you explain this answer?

Manoj Kulkarni answered  •  5 hours ago
Total Energy of a Satellite in Circular Orbit
To determine the total energy of a satellite in a circular orbit around the earth, we need to consider both its kinetic and potential energy.

Kinetic Energy
- The kinetic energy of the satellite is given by (1/2)mv^2, where m is the mass of the satellite and v is its velocity.

Potential Energy <
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What is basement membrane.?

Priya Datta answered  •  8 hours ago
Basement Membrane
The basement membrane is a thin, specialized extracellular matrix that separates and supports the epithelial and endothelial tissues from the underlying connective tissue. It plays a crucial role in maintaining tissue structure and function.
- Composition: The basement membrane is composed of two main layers - the basal lamina and the reticular lamina. The basal
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In a flask colourless N2O4 is in eqbm with brown coloured NO2.At eqbm when the flask is heated to 100 degree celcius,the brown colour deepens and on cooling it becomes coloured.Which statement is incorrect about this observat... more

Priya Datta answered  •  8 hours ago

b)paramagnetism increases on heating

- At 100 degrees Celsius, the equilibrium between N2O4 and 2NO2 shifts towards the formation of more NO2.
- NO2 is a paramagnetic molecule, meaning it is attracted to a magnetic field.
- As the concentration of NO2 increases with heating, so does the paramagnetism of the system.
- This increase in paramagnetism can be observed as a deepening of the brown color of the NO2 gas in the flask.
Therefore, the statement that paramagnetism increases on heating is correct in this scenario.

Which of the following is not stable? 1}[Sn(OH)6]2- 2}[SiCl6]2- 3}[SiF6]2- 4}[GeCl6]2-?

Priya Datta answered  •  8 hours ago
Instability of [Sn(OH)6]2-
Explanation:
• The stability of a complex ion is influenced by several factors, including the charge density, size, and electronegativity of the central metal ion.
• In the case of [Sn(OH)6]2-, the central metal ion is tin (Sn), which has a relatively high charge density due to its high atomic number and the presence of multiple positive ch
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In the following question, a statement of Assertion(A) is given followed by a corresponding statement of Reason(R).
Read the statements carefully, and mark the correct answer.
Assertion(A): In the descending limb of loop of Henle, the urnie is hypertonic, while in ascending limb of loops of Henle, the urine is hypotonic.
Reason(R): Descending limb is impermeable to Na+, while ascending limb is impermeable to H2O.
  • 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?

Priya Datta answered  •  9 hours ago
Explanation:

Descending Limb of Loop of Henle:
- The descending limb of the loop of Henle is permeable to water but impermeable to solutes such as Na+.
- As a result, water moves out of the descending limb due to the high osmolarity of the interstitium, making the urine hypertonic.

Ascending Limb of Loop of Henle:
- The ascending limb of th
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A typical flower with superior ovary and other floral parts inferior is - 
  • a)
    Polygamous
  • b)
    Hypogynous
  • c)
    Perigynous
  • d)
    Epigynous
Correct answer is option 'B'. Can you explain this answer?

Priya Datta answered  •  9 hours ago
Explanation:

Superior ovary:
- A flower with a superior ovary has its ovary positioned above the other floral parts such as sepals, petals, and stamens.

Inferior floral parts:
- When the other floral parts (sepals, petals, stamens) are positioned below the ovary, they are considered inferior.

Hypogynous flower:
- In a hypo
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If equal volume of 0.1 M NH4OH and 0.1 M HCI are mixed, then the pH of resulting mixture will be (Given: pKb(NH4OH) = 4.75, log 5 = 0.7 (1) 8.72 (2) 6.28. (3) 7.28 (4) 5.28?

Priya Datta answered  •  9 hours ago
Calculation of pH of resulting mixture:
- The given pKb of NH4OH is 4.75, which means pKa of NH4OH is 14 - 4.75 = 9.25.
- When NH4OH reacts with HCl, it forms NH4Cl and H2O.
- The NH4Cl formed is a salt of weak base NH4OH and strong acid HCl.
- Since NH4Cl is a salt of weak base and strong acid, it will undergo hydrolysis in water.
- The hydrolysis reaction of NH4Cl
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The antibody which can cross placental barrier is
  • a)
    IgA
  • b)
    IgE
  • c)
    IgM
  • d)
    IgG
Correct answer is option 'D'. Can you explain this answer?

Tejas Chatterjee answered  •  11 hours ago
Explanation:

IgG Antibody:
- IgG is the only antibody class that can cross the placental barrier.
- It provides passive immunity to the fetus, protecting it from various infections that the mother has immunity against.
- This transfer of IgG antibodies from the mother to the fetus occurs mainly during the third trimester of pregnancy.
- Once the baby is
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During DNA replication, Okazaki fragments are used to elongate    [2017]
  • a)
    The lagging strand towards replication fork
  • b)
    The leading strand away from replication fork
  • c)
    The lagging strand away from the replication fork
  • d)
    The leading strand towards replication fork.
Correct answer is option 'C'. Can you explain this answer?

Mansi Chakraborty answered  •  12 hours ago
Okazaki fragments in DNA replication
Okazaki fragments are short, newly synthesized DNA fragments that are formed on the lagging strand during DNA replication. They are essential for the replication of the lagging strand, which is synthesized discontinuously in the opposite direction of the replication fork.

Role of Okazaki fragments
- Okazaki fragments are used
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Directions: This question consist of two statements, each printed as Assertion and Reason. While answering this question, you are required to choose any one of the following four responses.

Assertion : At isoelectric point, the amino group does not migrate under the influence of electric field.
Reason : At isoelectric point, amino acid exists as a zwitterion.
  • a)
    If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
  • b)
    If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
  • c)
    If the Assertion is correct but Reason is incorrect.
  • d)
    If both the Assertion and Reason are incorrect.
Correct answer is option 'A'. Can you explain this answer?

Shreya Menon answered  •  15 hours ago
Explanation:

Assertion:
- The assertion states that at the isoelectric point, the amino group does not migrate under the influence of an electric field.
- This is because at the isoelectric point, the overall charge on the amino acid molecule is neutral.

Reason:
- The reason provided is that at the isoelectric point, the amino acid exists a
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The strongest acid among the following aromatic compounds is
  • a)
    p-chlorophenol
  • b)
    p-nitrophenol
  • c)
    m-nitrophenol
  • d)
    o-nitrophenol
Correct answer is option 'B'. Can you explain this answer?

Janani Choudhury answered  •  16 hours ago
Explanation:

p-nitrophenol is the strongest acid among the given aromatic compounds due to the presence of the nitro group (-NO2) which has a strong electron-withdrawing effect.

Reasons:
- p-nitrophenol has a nitro group (-NO2) attached to the para position of the phenol ring.
- The nitro group is a strong electron-withdrawing group due t
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What is the frequency of power in an AC circuit connected to a capacitor. Given, f= 50Hz, V= 220V A) 50 Hz B) 100 Hz C) zero D) 60 Hz?

Janani Choudhury answered  •  16 hours ago
Frequency of Power in an AC Circuit Connected to a Capacitor
Frequency of Power:
- The frequency of power in an AC circuit connected to a capacitor is the same as the frequency of the AC source providing power to the circuit.
- In this case, the given frequency is 50Hz.
Explanation:
- When an AC circuit is connected to a capacitor, the capacitor acts as a reactive c
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Depression in freezing point is 6K for Nacl solution .Of for water is 1.86K/kg mole ,amount of NaCl dissolved in 1kg of water is?

Janani Choudhury answered  •  16 hours ago
Calculation of Amount of NaCl Dissolved in 1kg of Water:
1. Given:
- Depression in freezing point = 6K
- Depression in freezing point for water = 1.86K/kg mole
2. Formula:
- \[ \Delta Tf = K_f \times m \]
- Where \(\Delta Tf\) = Depression in freezing point, \(K_f\) = Freezing point depression constant, and \(m\) = Molality of the solution
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In 1984, the bhopal gas tragedy took place bcs methyl isocyanate reacted with 1)CO2. 2)H2O. 3)DDT. 4)NH3?

Janani Choudhury answered  •  16 hours ago
Causes of the Bhopal Gas Tragedy
- Methyl Isocyanate Reacted with:
The Bhopal gas tragedy of 1984 was caused by a reaction of methyl isocyanate with water.

Explanation
- Methyl Isocyanate (MIC)
Methyl isocyanate, a highly toxic chemical used in pesticide production, was stored in large tanks at the Union Carbide plant in Bhopal.
-
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Due to an unintended reaction, water entered the storage tanks containing MIC, leading to a runaway exothermic reaction.
- Exothermic Reaction
The reaction between MIC and water released a large amount of heat, causing pressure to build up within the tanks.
- Release of Toxic Gas
As the pressure increased, the tanks ruptured, releasing a deadly cloud of toxic gas composed of MIC, hydrogen cyanide, and other chemicals.
- Impact
The gas cloud spread across the city of Bhopal, affecting thousands of people and resulting in one of the worst industrial disasters in history.

Conclusion
The Bhopal gas tragedy serves as a stark reminder of the importance of proper safety measures in chemical plants and the need for stringent regulations to prevent such disasters in the future.

Directions: In the following questions a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as:
Assertion (A) : Vasa efferentia develop from rete testis.
Reason (R) : Sperm conduction takes place by the ciliary current.
  • 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?

Janani Choudhury answered  •  16 hours ago
Explanation:

Development of Vasa Efferentia:
- Vasa efferentia develop from the rete testis, which is a network of tubules located in the mediastinum testis.
- The rete testis is responsible for collecting sperm from the seminiferous tubules within the testes.

Sperm Conduction:
- The function of the vasa efferentia is to conduct sperm from
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A garden sprinkler has 150 small holes, each of 2 mm2 area. If water is supplied at the rate of 0.3 litres/s, then find the average velocity of the spray.
  • a)
     300 cm/s
  • b)
     22.5 cm/s
  • c)
     0.1 cm/s
  • d)
     100 cm/s
Correct answer is option 'D'. Can you explain this answer?

Stuti Shah answered  •  16 hours ago
Given data:
- Number of holes = 150
- Area of each hole = 2 mm²
- Water supply rate = 0.3 litres/s

Calculating total area:
Total area of all holes = Number of holes x Area of each hole
Total area = 150 x 2 mm² = 300 mm² = 300 x 10^-6 m²

Calculating volume of water passing through the holes:
Volume of water passing through the
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Rain is falling vertically with a speed of 30 ms−1. A woman rides a bicycle with a speed of 12 ms−1 in east to west direction. In which direction she should hold her umbrella?
  • a)
    At an angle of tan−1(2/5) with the vertical towards the east.
  • b)
    At angle of tan−1(2/5) with the vertical towards the west.
  • c)
    At angle of tan−1 (5/2) with the vertical towards the east.
  • d)
    At angle of tan−1 (5/2) with the vertical towards the west.
Correct answer is option 'B'. Can you explain this answer?

Jyoti Shah answered  •  17 hours ago
Analysis:
To determine the direction in which the woman should hold her umbrella, we need to consider the relative motion of the rain with respect to the woman riding the bicycle.

Relative Velocity:
The woman is riding the bicycle at a speed of 12 m/s towards the west, and the rain is falling vertically at a speed of 30 m/s. The relative velocity of the rain with
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A hemispherical bowl just floats without sinking in a liquid of density 1.2 x 10 kg/m. If outer diameter and the density of the bowl are 1 m and 2 x 10 kg/m respectively, then the inner diameter of the bowl will be
  • a)
    0.94 m
  • b)
    0.97 m
  • c)
    0.98 m
  • d)
    0.99 m
Correct answer is option 'C'. Can you explain this answer?

Sneha Chopra answered  •  17 hours ago
Given data:
- Density of liquid: 1.2 x 10^3 kg/m^3
- Outer diameter of the bowl: 1 m
- Density of bowl: 2 x 10^3 kg/m^3

Concept:
- For an object to float in a liquid, the weight of the liquid displaced by the object must be equal to the weight of the object itself.
- The buoyant force acting on the bowl is equal to the weight of the liquid displace
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The coefficient of liner expansion of a cubical crystal along three mutually perpendicular direction is α1 αand α3. What is the coefficient of cubical expansion of crystal?
  • a)
    α+ α+ α3
  • b)
     
    α+ α- α3
  • c)
    α- α- α3
  • d)
     
    + α)/ α3
Correct answer is option 'A'. Can you explain this answer?

Dishani Chavan answered  •  18 hours ago
Calculation of Coefficient of Cubical Expansion
1. Given:
- Coefficient of linear expansion along three perpendicular directions: α1, α2, α3
2. Formula:
- The coefficient of cubical expansion (α) is given by the sum of the coefficients of linear expansion along three mutually perpendicular directions.
3. Calculation:
- α = α1 + α2 + α3
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If an element A atom has 18 protons, it follows that A has 18 electrons. So, the number of electrons in an A+ will be -
  • a)
    21
  • b)
    20
  • c)
    19
  • d)
    17
Correct answer is option 'D'. Can you explain this answer?

Dishani Chavan answered  •  18 hours ago
Explanation:

Number of Electrons in A+ ion:
- An element A with 18 protons will have 18 electrons in its neutral state.
- When an element loses one electron to form a +1 ion, it will have one less electron than its neutral state.
- Therefore, the number of electrons in A+ ion will be 18 - 1 = 17 electrons.
Therefore, the correct answer is option 'D' - 1
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In SI unit system, pascal is the unit of
  • a)
    pressure
  • b)
    work
  • c)
    energy
  • d)
    power
Correct answer is option 'A'. Can you explain this answer?

Dishani Chavan answered  •  18 hours ago
Pressure:
Pascal is the unit of pressure in the SI unit system. Pressure is defined as the force applied per unit area. The SI unit of pressure is pascal, which is equal to one newton per square meter. This unit is named after Blaise Pascal, a French mathematician, physicist, and philosopher.

Relation to Force and Area:
Pressure can be calculated by dividing the
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What are the components required to calculate the momentum of a body?
  • a)
    Mass and acceleration
  • b)
    Velocity and mass
  • c)
    Displacement and mass
  • d)
    None of the mentioned
Correct answer is option 'B'. Can you explain this answer?

Dishani Chavan answered  •  18 hours ago
Components required to calculate the momentum of a body:
- Velocity and mass: The correct components required to calculate the momentum of a body are velocity and mass.

Explanation:
- Momentum is defined as the product of an object's mass and its velocity. Mathematically, momentum (p) can be calculated using the formula:
p = m * v
where,
p
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Select the correct statement for the given complexes [Fe(CN)6]4-, [Ni(CN)4]2- and [Ni(CO)4]
  • a)
    All have identical geometry
  • b)
    All are heteroleptic complex
  • c)
    All are diamagnetic
  • d)
    All obey EAN rule
Correct answer is option 'C'. Can you explain this answer?

Dishani Chavan answered  •  18 hours ago
Geometry:
- [Fe(CN)6]4-, [Ni(CN)4]2-, and [Ni(CO)4] complexes do not have identical geometry.
- [Fe(CN)6]4- has an octahedral geometry due to the presence of 6 ligands, while [Ni(CN)4]2- has a square planar geometry as it has 4 ligands, and [Ni(CO)4] has a tetrahedral geometry because of the 4 ligands.

Heteroleptic Complexes:
- [Fe(CN)6]4-, [Ni(CN)4]2-, and
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Direction: In the following questions a statement of assertion (A) is followed by a statement of reason (R). Mark the correct choice as :
Assertion (A): The offspring of a cross made between the plants having two contrasting characters shows only one character without any blending.
Reason (R): The factor controlling any character is discrete and independent.
  • 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?

Dishani Chavan answered  •  18 hours ago
Explanation:

Assertion (A) and Reason (R) Analysis:
- The assertion states that the offspring of a cross made between plants with two contrasting characters only show one character without any blending.
- The reason provided is that the factor controlling any character is discrete and independent.

Analysis of Correct Answer:
- Option (A) is
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What is correct about self-incompatibility?
  • a)
    It is due to the non-synchronization of pollen release and stigma receptivity.
  • b)
    It is a genetic mechanism.
  • c)
    It is seen only in unisexual flowers.
  • d)
    It is due to the anther and stigma are placed at different positions.
Correct answer is option 'B'. Can you explain this answer?

Dishani Chavan answered  •  18 hours ago
Genetic Mechanism of Self-Incompatibility
Self-incompatibility is a genetic mechanism that prevents self-fertilization in plants. It involves the recognition and rejection of self-pollen to promote outcrossing, which increases genetic diversity within a population.

Recognition of Self-Pollen
Plants have a genetic system that allows them to distinguish between sel
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Which of the following reagents convert propene to 1-propanol?
  • a)
    H2O, H2SO4
  • b)
    aqueous KOH
  • c)
    MgSO4, NaBH4/H2O
  • d)
    B2H6, H2O2, OH
Correct answer is option 'D'. Can you explain this answer?

Dishani Chavan answered  •  18 hours ago
Conversion of Propene to 1-Propanol:
To convert propene to 1-propanol, the following reagents are used:

B2H6:
- Borane (B2H6) is used as a reducing agent in this reaction.
- It adds to the double bond of propene to form a trialkylborane intermediate.

H2O2:
- Hydrogen peroxide (H2O2) is used as an oxidizing agent in this reaction.
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Two parallel infinite line charges + λ and -λ are placed with a separation distance R in free space. Then etelectric field exactly mid - way between the two line charges is 
  • a)
     zero
  • b)
    2λ/πε0R
  • c)
    λ/πε0R
  • d)
    λ/2πε0R
Correct answer is option 'B'. Can you explain this answer?

Dishani Chavan answered  •  18 hours ago
Explanation:

Electric field due to each line charge:
- The electric field due to a line charge is given by E = λ/2πε0r, where r is the distance from the line charge.
- For the positive line charge (+λ), the electric field points away from the line charge.
- For the negative line charge (-λ), the electric field points towards t
... more

Short note on skeleton system?

Dishani Chavan answered  •  18 hours ago
The Skeletal System
The skeletal system is a complex structure made up of bones, joints, cartilage, and ligaments that provides support and protection for the body's organs. It also plays a crucial role in movement, blood cell production, and mineral storage. Here is a detailed explanation of the skeletal system:

Bones
- Bones are the primary components of the sk
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Bryophytes are called amphibians of the plant kingdom because:
  • a)
    They have gills and lungs.
  • b)
    They have dry surface.
  • c)
    They need water for spore dispersal.
  • d)
    They need water for sexual reproduction.
Correct answer is option 'D'. Can you explain this answer?

Dishani Chavan answered  •  18 hours ago
Why Bryophytes are called amphibians of the plant kingdom?
  • Need for water in sexual reproduction: Bryophytes, which include mosses, liverworts, and hornworts, require water for their sexual reproduction process. They reproduce through the production of motile sperm that swim through a film of water to reach the egg for fertilization. This dependence on water for the tran... more


Therefore, the term "amphibians of the plant kingdom" is used to describe bryophytes due to their need for water in sexual reproduction, similar to amphibians' reliance on water for certain aspects of their life cycle.
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