datavorous/entrance-exam-dataset huggingface dataset:
In the electron transport chain the correct sequence of electron acceptor is

Options:
A Cytochrome a, a3, b, c
B Cytochrome b, c, a, a3
C Cytochrome b, c3, a, a3
D Cytochrome c, b, a, a3

The correct answer is:
Cytochrome b, c, a, a3

Solution:
ETS consists of 5 complex :
Complex I - NADH is oxidised by transferring electrons to Ubiquinone in presence of NADH dehydrogenase.
Complex II - FADH2 is oxidised by transferring electrons to Ubiquinone.
Complex III - Reduced ubiquinone (ubiquinol) is oxidised by transferring electrons to cytochrome c via
cytochrome bc1 complex. Cytochrome c is a small protein attached to the outer surface of the inner
membrane and acts as a mobile carrier for the transfer of electrons from Complex III to Complex IV.
Complex IV - It is cytochrome c oxidase complex containing cytochromes a and a3 and two copper centres.
Complex V - ATP synthase.

Topic: Biology, Respiration in Plants, NEET
In the electron transport chain, the cytochrome where the terminal oxidation takes place is

Options:
A Cyt b
B Cyt a3
C cyt a
D Cyt c

The correct answer is:
Cyt a3

Solution:
The energy within NADH2 and FADH2 are released by oxidizing them through an electron transport system. The system has four complexes via which the high energy electron is passed ultimately accepted by oxygen. Each complex has a set of pigments. The last complex, complex IV has the pigment cytochrome and a3 where cyt a3 is the last cytochrome in the ETS.

Topic: Biology, Respiration in Plants, NEET
In the electron transport system, a molecule of ATP is formed when an electron passes from:

Options:
A Cytochrome-c to cytochrome-a
B Cytochrome-a to cytochrome-c
C Cytochrome-b to cytochrome-c1
D Cytochrome-c to cytochrome-b

The correct answer is:
Cytochrome-b to cytochrome-c1

Solution:
In all, 3 ATP molecules are formed in the electron transfer system:
i. First between NADH2 and FMN.
ii. Second between cytochrome-b and cytochrome-c1
iii. Third between cytochrome-a and cytochrome-a3

Topic: Biology, Respiration in Plants, NEET
In the electron transport system present in the inner mitochondrial membrane, complexes I and IV are respectively

Options:
A NADH dehydrogenase and FADH2
B NADH2 and NADH dehydrogenase
C NADH dehydrogenase and cytochrome-c oxidase complex
D NADH dehydrogenase and ATP synthase

The correct answer is:
NADH dehydrogenase and cytochrome-c oxidase complex

Solution:
Complex I of the electron transport system (ETS) is NADH dehydrogenase, which oxidizes NADH produced in the mitochondrial matrix during the citric acid cycle. Cytochrome c oxidase or complex IV catalyzes the final step in the mitochondrial electron transfer chain and is regarded as one of the major regulation sites for oxidative phosphorylation.

Topic: Biology, Respiration in Plants, NEET
In the electrophilic addition of concentrated sulphuric acid to alkenes, which atom in sulphuric acid acts as an electrophile?

Options:
A Hydrogen
B Sulfur
C Oxygen
D Carbon

The correct answer is:
Oxygen

Solution:
In the electrophilic addition reaction with concentrated sulphuric acid, the oxygen atom in sulfuric acid acts as an electrophile.

Topic: Chemistry, Hydrocarbons, NEET
In the embryo of typical dicot and monocot, true homologous structures are

Options:
A Coleorhiza and coleoptile
B Coleoptile and scutellum
C Cotyledon and hypocotyl
D Cotyledon and scutellum

The correct answer is:
Cotyledon and scutellum

Solution:
Dicot embryo consists of two cotyledons and monocot embryo consist of single cotyledon known as scutellum, which forms a shield shaped structure between endosperm and embryo. Both are homologous as both have same origin and structure but perform different function. Coleorrhizae and coleoptiles are foliar structure present at root apex and shoot apex.

Topic: Biology, Sexual Reproduction in Flowering Plants, NEET
In the energy band diagram of a material shown below, the open circles and filled circles denote holes and electrons respectively. The material is

Options:
A an insulator
B a metal
C an $n$-type semiconductor
D a p-type semiconductor.

The correct answer is:
a p-type semiconductor.

Solution:
In this Band diagram, number of holes in valence band are more as compared to no.number of electrons in the conduction band. So, it is a p-type semiconductor.

Topic: Physics, Semiconductors, NEET, NEET 2007
In the enzyme which catalyses the breakdown of: $\mathrm{H}_2 \mathrm{O}_2 \rightarrow \mathrm{H}_2 \mathrm{O}+\mathrm{O}_2$ the prosthetic group is :

Options:
A Nicotinamide adenine dinucleotide
B Haem
C Zinc
D Niacin

The correct answer is:
Haem

Solution:
The enzyme which catalyse the breakdown of $\mathrm{H}_2 \mathrm{O}_2$ as :
$\mathrm{H}_2 \mathrm{O}_2 \longrightarrow \mathrm{H}_2 \mathrm{O}+\mathrm{O}_2$
is called Catalase which have prosthetic group Haem. This enzyme is activated by iron. The breakdown occurs inside peroxisome during photorespiration.

Topic: Biology, Biomolecules (B), NEET, NEET 2022 (Phase 2)
In the equation, dN/dt = rN

Options:
A 'r' is called the âintrinsic rate of natural increaseâ.
B 'r' is the parameter chosen for assessing impacts of any biotic factor on population growth.
C 'r' is the parameter chosen for assessing impacts of an abiotic factor on population growth.
D All of these

The correct answer is:
All of these

Solution:
The equation, dN/dt = rN describes the exponential or geometric growth pattern of a population and results in a J-shaped curve when N is plotted with relation to time.
The 'r' in this equation is called the âintrinsic rate of natural increaseâ and is a very important parameter chosen for assessing impacts of any biotic or abiotic factor on population growth.

Topic: Biology, Organisms and Populations, NEET
In the equation for Haber's process, what is the role of Fe(s)?

Options:
A Catalyst
B Promoter
C Poison
D Adsorbent

The correct answer is:
Catalyst

Solution:
The equation for Haber's process indicates that Fe(s) acts as a catalyst.

Topic: Chemistry, Surface Chemistry, NEET
In the equation for S-shaped population growth dNdt=rNK-NK, r represents

Options:
A Carrying capacity
B Environmental resistance
C Biotic potential
D Population size

The correct answer is:
Biotic potential

Solution:
In the logistic growth, per capita growth rate (r) depends on population size (N) and how close it is to carrying capacity (K). 'r' is the per capita rate of increase for a particular species under ideal conditions, and it varies from species to species. For instance, bacteria can reproduce much faster than humans and would have a higher maximum per capita rate of increase. The maximum population growth rate for a species is called its biotic potential. 'r' represents the intrinsic growth rate of a population.

Topic: Biology, Organisms and Populations, NEET
In the equation GPP - R = NPP

GPP is Gross Primary Productivity

NPP is Net Primary Productivity

R here is :

Options:
A Reproductive allocation
B Photosynthetically active radiation
C Respiratory quotient
D Respiratory loss

The correct answer is:
Respiratory loss

Solution:
Gross primary productivity of an ecosystem is the rate of production of organic matter during photosynthesis. A considerable amount of GPP is utilised by plants in respiration. Gross primary productivity minus respiration losses (R), is the net primary productivity (NPP).

GPP = NPP + RorGPP - R = NPP

The Net primary productivity (NPP) is the available biomass for the consumption to heterotroph (herbivores and decomposers).

Topic: Biology, Ecosystem, NEET, NEET 2023 (All India)
In the equation H2 + Pd(aq) → Pd(s) + 2H(aq), what does "Pd" represent?

Options:
A Palladium
B Platinum
C Phosphorus
D Potassium

The correct answer is:
Palladium

Solution:
In the equation, "Pd" represents palladium, which is reduced from its aqueous ion form by dihydrogen.

Topic: Chemistry, Hydrogen, NEET
In the equation Kb = [M+][OH-] / [MOH], what does 'Kb' represent?

Options:
A The equilibrium constant for the acid-dissociation equilibrium.
B The equilibrium constant for base ionization.
C The extent of ionization of a weak base.
D The initial concentration of the undissociated base, MOH.

The correct answer is:
The equilibrium constant for base ionization.

Solution:
In the equation Kb = [M+][OH-] / [MOH], 'Kb' represents the equilibrium constant for base ionization.

Topic: Chemistry, Ionic Equilibrium, NEET
In the equation of the species-area relationship, the letter 'C' and 'Z' represent:

Options:
A C = Regression coefficient, Z = Y-intercept
B C = Slope of the line, Z = Regression coefficient
C C = Y-intercept, Z = Slope of the line (regression coefficient)
D Both B and C

The correct answer is:
C = Y-intercept, Z = Slope of the line (regression coefficient)

Solution:
Biodiversity includes all the flora and fauna on Earth. All the varieties of organisms come under biodiversity. German naturalist Alexander von Humboldt made the observation regarding the relationship between species richness and the area of the habitat. As per his observation, species richness increased with increasing area of habitat upto a limit. When plotted in a graph, this relationship forms a rectangular hyperbola with the equation S = CAZ. On a log scale, the relationship is a straight line having the equation.
log S=log C+Z log A. S= species richness, A= area of region, C=Y-intercept and Z= regression co-efficient (Slope). Ecologists' study has shown that value of Z lies in the range of 0.1-0.2 irrespective of the organism group or region unless the area is very large like entire continents.

Topic: Biology, Biodiversity and its Conservation, NEET
In the equation p+Î±V2 V-b=constant, the unit of Î± is

Options:
A dyneÃcm5
B dyneÃcm4
C dyne cm-3
D dyne cm-2

The correct answer is:
dyne×cm4

Solution:
According to the principle of dimensional homogeneity, p=Î±V2
â Î±=p V2=ML-1 T-2 L6=ML5T-2
Hence, the units of Î±=gmÃcm5Ãs-2
=dyneÃcm4

Topic: Physics, Units and Dimensions, NEET
In the equilibrium of camphor, what are the physical states involved?

Options:
A Camphor (solid) and camphor (vapor)
B Camphor (liquid) and camphor (solid)
C Camphor (gas) and camphor (liquid)
D Camphor (solid) and camphor (liquid)

The correct answer is:
Camphor (solid) and camphor (vapor)

Solution:
Camphor (solid) and camphor (vapor) are involved in the equilibrium.

Topic: Chemistry, Chemical Equilibrium, NEET
In the estimation of sulphur by Carius method, 0.468 g of an organic sulphur compound afforded 0.668 g of barium sulphate. Find out the percentage of sulphur in the given compound.

Options:
A % of sulphur = 85.35
B % of sulphur = 36.12
C % of sulphur = 19.66
D % of sulphur = 48.57

The correct answer is:
% of sulphur = 19.66

Solution:
Correct Option is : (C)
% of sulphur = 19.66

Topic: Chemistry, General Organic Chemistry, NEET
In the estimation of sulphur organic compound on treating with conc. HNO3 is converted to

Options:
A SO2
B H2S
C H2SO4
D SO3

The correct answer is:
H2SO4

Solution:
In carius method sulphur of organic compound is converted in to H2SO4
S+H2O+3[O] âÎHNO3H2SO4

Topic: Chemistry, General Organic Chemistry, NEET
In the evolution of man, several changes occurred in the ancestral characters. Which one of the following changes is irrelevant in this context?

Options:
A Loss of tail from body
B Increase in the ability to communicate with others and develop community behaviour
C Arboreal mode of lifestyle
D Perfection in the structure and working of hand for tool-making

The correct answer is:
Arboreal mode of lifestyle

Solution:
Arboreal mode of lifestyle: who spend the majority of their lives in trees. They eat, sleep and play in the tree canopy.
Over the years we have started linig in the houses made by man. we don't lead arboreal lifestyle any more.

Topic: Biology, Evolution, NEET
In the example of ABO blood grouping, how many alleles govern the same character?

Options:
A One
B Two
C Three
D Four

The correct answer is:
Three

Solution:
The example of ABO blood grouping has three alleles governing the same character.

Topic: Biology, Principles of Inheritance and Variation, NEET
In the experiment to determine the focal length of a concave mirror by graphical methods the u - v graph is

Options:
A A straight line
B A circle
C An ellipse
D None of these

The correct answer is:
None of these

Solution:
In the experiment to determine the focal length of a concave mirror by graphical methods the u - v graph is hyperbolic.
None of these

Topic: Physics, Experimental Physics, NEET
In the exponential growth equation Nt=N0ert, e, represents:

Options:
A The base of number logarithms
B The base of exponential logarithms
C The base of natural logarithms
D The base of geometric logarithms

The correct answer is:
The base of natural logarithms

Solution:
The equation describes the exponential or geometric growth pattern of a population. This results in the typical J-shaped curve with the equation: Nt=N0ert. In this equation, e is the base of natural logarithms (2.71828).

Topic: Biology, Organisms and Populations, NEET, NEET 2021
In the extended pH scale for the hydrogen ion concentration, what does pKb represent?

Options:
A The concentration of hydroxide ions (OH-) in a solution.
B The concentration of hydrogen ions (H+) in a solution.
C The extent of ionization of a weak base.
D The extent of ionization of a strong acid.

The correct answer is:
The extent of ionization of a weak base.

Solution:
pKb represents the extent of ionization of a weak base on the extended pH scale.

Topic: Chemistry, Ionic Equilibrium, NEET
In the extraction of copper from its sulphide ore, the metal is finally obtained by the reduction of cuprous oxide with:

Options:
A Iron (II) sulphide
B Carbon monoxide
C Copper (I) sulphide
D Sulphur dioxide

The correct answer is:
Copper (I) sulphide

Solution:
One of the process in extraction of copper is self-reduction of the ore after roasting.
Cu2S+2Cu2O⟶6Cu+SO2↑

Topic: Chemistry, General Principles and Processes of Isolation of Metals, NEET, NEET 2015 (Phase 2)
In the extraction of metals such as iron, what role does calcium carbonate play?

Options:
A It acts as a reducing agent
B It acts as a flux along with magnesium carbonate
C It acts as a catalyst
D It acts as a solvent

The correct answer is:
It acts as a flux along with magnesium carbonate

Solution:
Calcium carbonate, along with magnesium carbonate, is used as a flux in the extraction of metals such as iron.

Topic: Chemistry, s Block Elements, NEET
In the F2 generation, genotypic and phenotypic ratios are identical in case of

Options:
A Complementary genes
B Mendelian dihybrids
C Mendelian monohybrids
D Incomplete dominance

The correct answer is:
Incomplete dominance

Solution:
Incomplete or partial or intermediate dominance is observed when a red-flowered plant of Mirabilis jalapa is crossed with white-flowered plants. The plants in of F1 generation have pink flower and on selfing, with pink-flowered plants, the red, pink, and white-flowered plants are produced in 1:2:1 genotypic as well as phenotype ratio in the F2 generation.

Topic: Biology, Principles of Inheritance and Variation, NEET
In the female frog, where do the ureters and oviduct open?

Options:
A In the cloaca
B In the urinary bladder
C In the rectum
D Separately in the cloaca

The correct answer is:
Separately in the cloaca

Solution:
In the female frog, the ureters and oviduct open separately in the cloaca, while in the male frog, the ureters open into the cloaca as part of the urogenital duct.

Topic: Biology, Structural Organisation in Animals, NEET
In the figure, a charged sphere of mass m and charge q starts sliding from rest on a vertical fixed circular track of radius R from the position shown. There exists a uniform and constant horizontal magnetic field of induction B. The maximum force exerted by the track on the sphere is -

Options:
A mg
B 3mg- qB2gR
C 3mg+qB2gR
D mg- qB2gR

The correct answer is:
3mg+qB2gR

Solution:
Fm=q v B (directed radially outward)
∵ N- mg sin⁡θ- q v B=mv2R
or N=mv2R+mg sin⁡θ+qvB
θ=π/2
Hence at θ=π/2
Nmax=2mgRR+mg+qB2gR
=3mg+qB2gR
Nmax=3mg+qB2gR

Topic: Physics, Magnetic Effects of Current, NEET
In the figure, a smooth pulley of negligible weight is suspended by a spring balance. Masses of 1 kg and 5 kg are attached to the opposite ends of a string passing over the pulley and move with some acceleration. During their motion, the spring balance reads a weight of

Options:
A 6 kgf
B Less than 6 kgf
C More than 6 kgf
D May be more or less than 6 kgf

The correct answer is:
Less than 6 kgf

Solution:
Spring balance reading is equal to 2T

tension in the string=2m1m2m1+m2=2Ã5Ã16=53 Kgf
reading of spring balance= 2T=2Ã53=103 Kgf

Topic: Physics, Laws of Motion, NEET
In the figure, a sphere of radius 2 m rolls on a plank. The accelerations of the sphere and the plank are indicated. The value of angular acceleration is

Options:
A 2 rad s-2
B 4 rad s-2
C 3 rad s-2
D 1 rad s-2

The correct answer is:
3 rad s-2

Solution:
As the sphere rolls, the lowest point of the sphere should have the same acceleration as the plank.
Hence, a1=αR-a2
2=2α-4

⇒α=3 rad s-2

Topic: Physics, Rotational Motion, NEET
In the figure given, A and B are two particles having same magnitude of angular velocity in opposite sense, at t=0, then VâA-VâB at t=Ï2Ï sec is

Options:
A -ω R1i^+ωR2i^
B ω R1i^-ωR2j^
C Ï R1j^-ÏR2i^
D Ï R1j^+ÏR2j^

The correct answer is:
-ω R1i^+ωR2i^

Solution:
t=π2ω
V→A=ωR1-i^
V→B=ωR2-i^

Topic: Physics, Laws of Motion, NEET
In the figure, if a parallel beam of white light is incident on the plane of the slits S1 and S2 then the distance of the nearest white spot on the screen from O is [Assume D>>d, d>>λ ]

Options:
A 0
B 3d 8
C d 2
D d 8

The correct answer is:
3d 8

Solution:
White spot on screen would be central maximum where
Δ x = 0 y = d 2 - d 8 = 3d 8

Topic: Physics, Wave Optics, NEET
In the figure, mA=2 kg and mB=4 kg . For what minimum value of F,A starts slipping over B g=10m s-2 ?

Options:
A 24 N
B 36 N
C 12 N
D 20 N

The correct answer is:
36 N

Solution:
Maximum frictional force between A and B could be
f1=μ1mAg=0.2210 N
f1=4 N
Acceleration when frictional force is maximum,
a=f1mA
a=42=2m/s2
Fictional force between ground and B
f2=μ2mA+mBg
f2=0.42+410
f2=24 N

Therefore for the entire system,
F-f2=mA+mBa
F-24=2+42
F=36 N

Topic: Physics, Laws of Motion, NEET
In the figure, mA=2 kg and mB=4 kg. For what minimum value of force F, A starts slipping over B g=10 m s-2

Options:
A 24Â N
B 36 N
C 12Â N
D 20Â N

The correct answer is:
36 N

Solution:
For A, mAa=fL1
mAa=Î¼1mAg
a=Î¼1g
For B,
F-fL1+fL2=mBa
F=Î¼1mAg+Î¼2mA+mBg+mBÎ¼1g
F=Î¼1+Î¼2mA+mBg
F=0.2+0.42+410
F=36 N

Topic: Physics, Laws of Motion, NEET
In the figure, potential difference between A and B is:

Options:
A 10 V
B 5 V
C 15 V
D 0 V

The correct answer is:
10 V

Solution:
Diode is in forward bias, so it will behave as simple wire so,
So, Vab=305+10Ã5=10 V

Topic: Physics, Semiconductors, NEET
In the figure, potential difference between A and B is:

Options:
A 10V
B 5V
C 15V
D 0V

The correct answer is:
10V

Solution:
Diode is in forward bias, so it will behave as simple wire so,

So, Vab=305+10×5=10V

Topic: Physics, Semiconductors, NEET
In the figure shown a current I1 is established in the long straight wire AB. Another wire CD carrying current I2 is placed in the plane of the paper. The line joining the ends of the wire is perpendicular to the wire AB. The resultant force on the wire CD is :

Options:
A Zero
B Towards negative x-axis
C Towards positive y-axis
D None of these

The correct answer is:
None of these

Solution:
Diagram of force acting on wire will be as shown in diagram

but magnitude of all elemental forces are not equal and not even symmetrically distributed so no componentof force will get canceled completely so resultant, will have component in x as well as y

Topic: Physics, Magnetic Effects of Current, NEET
In the figure shown, all surfaces are smooth. Acceleration of mass '4m', when the system Is released from rest will be

Options:
A 2g9
B 4g9
C 2g3
D g3

The correct answer is:
4g9

Solution:
Tension in the string will be T everywhere
mg-T=may ...(i)
2T=5max ...(ii)
Also, -ax-ax+ay=0
or ay=2ax ...(iii)
Solving (i), (ii), (iii)
ax=2g9
ay=4g9

Topic: Physics, Laws of Motion, NEET
In the figure shown below, an ideal gas is carried around the cyclic process. How much work is done in one cycle if P0=8 atm and V0=7.00  litre?

Options:
A 5656 J
B -5656 J
C 10600 J
D 11300 J

The correct answer is:
-5656 J

Solution:
Work done is area under the curve
W=P0V0
=-8Ã105Ã1.01Ã7Ã10-3
W=-56Ã1.01Ã102 J
W=-5656 J

Topic: Physics, Thermodynamics, NEET
In the figure shown below each battery has emf=5 V. Then the magnetic field at P is

Options:
A zero
B 10μ0R1(4π)(.2)
C 20μ0(R1⁡+R2⁡)(.8π)
D none of these

The correct answer is:
zero

Solution:
In both the loop
âV=0
Therefore Inet=0
since the current in both the loops is zero, the field at the point P will be zero.

Topic: Physics, Current Electricity, NEET
In the figure shown here, what is the equivalent focal length of the combination of lenses (Assume that all layers are thin)?

Options:
A -50 cm
B 40 cm
C -40 cm
D -100 cm

The correct answer is:
-100 cm

Solution:
The focal length fL of the left plano-concave lens can be calculated as follows-

1fL=n-11R1-1R2= 1.6-11∞-120 cm= -0.620 cm ...1

The focal length fM of the middle bi-convex lens can be calculated as follows-

1fM=n-11R1-1R2= 1.5-1120 cm-1-20 cm= 0.510 cm ...2

The focal length fR of the right plano-concave lens can be calculated as follows-

1fR=n-11R1-1R2= 1.6-11-20 cm-1∞= -0.620 cm ...3

Hence, the effective focal length f of the combination of lenses can be calculated as follows-

1f=1fL+1fM+1fR= -0.620 cm+0.510 cm-0.620 cm= -0.110 cm⇒f= -100 cm

Topic: Physics, Ray Optics, NEET, NEET 2023 (All India)
In the figure shown, the capacity of the condenser C is 2 Î¼F. The current in 2 Î© resistor is

Options:
A 9 A
B 0.9 A
C 19 A
D 10.9 A

The correct answer is:
0.9 A

Solution:
Resistance in uppermost branch R = 2Ã32+3=65=1.2 Î©
After a long time, branch with the capacitor can be considered open circuited

Hence,
Req = 2.8+1.2 = 4
I= VR=64=32 A
I2Î©= IR2R1+R2=32Ã35 A
I2Î© = 910=0.9 A

Topic: Physics, Current Electricity, NEET
In the figure shown the velocity of lift is 2 m s-1 upwards while the string is winding on the motor shaft with velocity 2 m s-1 and block A is moving downwards with a velocity of 2 m s-1, then find out the velocity of block B.

Options:
A 2 m s-1↑
B 2 m s-1↓
C 4 m s-1â
D 8 m s-1â

The correct answer is:
8 m s-1â

Solution:
Let, v B = velocity of block B
v A L = velocity of block A with respect to lift
v L = velocity of lift
v B =− v A L + v L + v winding
=−( v A − v L )+ v L + v winding
=−( −2−2 )+2+2
=8 m s-1

Topic: Physics, Laws of Motion, NEET
In the figure shown water is filled in a symmetrical container. Four pistons of equal area A are used at the four openings to keep the water in equilibrium. Now an additional force F is applied at each piston. The increase in the pressure at the centre of the container due to this addition is

Options:
A FA
B 2FA
C 4FA
D 0

The correct answer is:
FA

Solution:
From Pascal's law, if pressure is increased at one point then it gets increased at all points in the entire liquid by the same amount. Therefore if an additional force F is applied at each piston, then pressure at each point and therefore also at the centre of the container increases by the same amount of FA.

Topic: Physics, Mechanical Properties of Fluids, NEET
In the figure, the ball A is released from rest when the spring is at its natural (unstretched) length. For the block B of mass M to leave contact with the ground at some stage, the minimum mass of A must be

Options:
A 2M
B M
C M2
D M4

The correct answer is:
M2

Solution:
The spring will exert maximum force when the ball is at its lowest position. If the ball has descended through a distance x to reach the position.
mgx=12Kx2 or x=2mgk.....(i)
For block B to leave contact spring force, Kx=Mg.....(i)
Comparing equations (i) and (ii), m=M2

Topic: Physics, Work Power Energy, NEET