Class 11 • Physics

Laws of Motion

Chapter-4

262 Questions

0 Video Solutions

52 Easy209 Medium1 Hard

Practice Questions

Click on any question to view the complete question with options and detailed solution.

Options:

A) 25

B) 12.5

Options:

110

EasyJEE Mains2021

Statement : 1If three forces ${\overrightarrow F _1},{\overrightarrow F _2} and {\overrightarrow F _3} are represented by three sides of a triangle and {\overrightarrow F _1} + {\overrightarrow F _2} = - {\overrightarrow F _3}, then these three forces are concurrent forces and satisfy the condition for equilibrium.Statement : 2A triangle made up of three forces {\overrightarrow F _1}, {\overrightarrow F _2} and {\overrightarrow F _3}$ as its sides taken in the same order, satisfy the condition for translatory equilibrium.In the light of the above statements, choose the most appropriate answer from the options given below :

Options:

A) Statement - I is false but Statement - II is true

B) Statement - I is true but Statement - II is false

C) Both Statement-I and Statement-II are false

D) Both Statement-I and Statement-II are true

111

MediumJEE Mains2021

The boxes of masse 2 kg and 8 kg are connected by a massless string passing over smooth pulleys. Calculate the time taken by box of mass 8 kg to strike the ground starting from rest. (use g = 10 m/s2)

Options:

A) 0.34 s

B) 0.2 s

C) 0.25 s

D) 0.4 s

112

MediumJEE Mains2021

The initial mass of a rocket is 1000 kg. Calculate at what rate the fuel should be burnt so that the rocket is given an acceleration of 20 ms-2. The gases come out at a relative speed of 500 ms$-$1 with respect to the rocket : [Use g = 10 m/s2]

Options:

A) 6.0 $\times 102 kg s-$1

B) 500 kg s$-$1

C) 10 kg s$-$1

D) 60 kg s$-$1

113

MediumJEE Mains2021

A particle of mass M originally at rest is subjected to a force whose direction is constant but magnitude varies with time according to the relation $F = {F_0}\left[ {1 - {{\left( {{{t - T} \over T}} \right)}^2}} \right]$Where F0 and T are constants. The force acts only for the time interval 2T. The velocity v of the particle after time 2T is :

Options:

A) 2F0T/M

B) F0T/2M

C) 4F0T/3M

D) F0T/3M

114

EasyJEE Mains2021

A force $\overrightarrow F = (40\widehat i + 10\widehat j)N acts on a body of mass 5 kg. If the body starts from rest, its position vector \overrightarrow r $ at time t = 10 s, will be :

Options:

A) (100\widehat i + 400\widehat j)m

B) (100\widehat i + 100\widehat j)m

C) (400\widehat i + 100\widehat j)m

D) (400\widehat i + 400\widehat j)m

115

EasyJEE Mains2021

A steel block of 10 kg rests on a horizontal floor as shown. When three iron cylinders are placed on it as shown, the block and cylinders go down with an acceleration 0.2 m/s2. The normal reaction R' by the floor if mass of the iron cylinders are equal and of 20 kg each, is ____________ N. [Take g = 10 m/s2 and $\mu$s = 0.2]

Options:

A) 686

B) 684

C) 714

D) 716

116

EasyJEE Mains2021

A block of mass m slides along a floor while a force of magnitude F is applied to it at an angle $\theta as shown in figure. The coefficient of kinetic friction is \mu$k. then, the block's acceleration 'a' is given by :(g is acceleration due to gravity)

Options:

A) {F \over m}\cos \theta + {\mu _K}\left( {g - {F \over m}\sin \theta } \right)

B) {F \over m}\cos \theta - {\mu _K}\left( {g - {F \over m}\sin \theta } \right)

C) -{F \over m}\cos \theta - {\mu _K}\left( {g - {F \over m}\sin \theta } \right)

D) {F \over m}\cos \theta - {\mu _K}\left( {g + {F \over m}\sin \theta } \right)

117

MediumJEE Mains2021

Two masses A and B, each of mass M are fixed together by a massless spring. A force acts on the mass B as shown in the figure. If the mass A starts moving away from mass B with acceleration 'a', then the acceleration of mass B will be :

Options:

A) {{MF} \over {F + Ma}}

B) {{F + Ma} \over M}

C) {{Ma - F} \over M}

D) {{F - Ma} \over M}

118

MediumJEE Mains2021

A particle is projected with velocity v0 along x-axis. A damping force is acting on the particle which is proportional to the square of the distance from the origin i.e. ma = $- \alpha$x2. The distance at which the particle stops :

Options:

A) {\left[ {{{3mv_0^2} \over {2\alpha }}} \right]^{{1 \over 3}}}

B) {\left( {{{2{v_0}} \over {3\alpha }}} \right)^{{1 \over 3}}}

C) {\left( {{{3v_0^2} \over {2\alpha }}} \right)^{{1 \over 2}}}

D) {\left( {{{2v_0^2} \over {3\alpha }}} \right)^{{1 \over 2}}}

119

MediumJEE Mains2020

A particle moving in the xy plane experiences a velocity dependent force $\overrightarrow F = k\left( {{v_y}\widehat i + {v_x}\widehat j} \right) , where vx and vy are the x and y components of its velocity \overrightarrow v . If \overrightarrow a $ is the acceleration of the particle, then which of the following statements is true for the particle?

Options:

A) kinetic energy of particle is constant in time

B) quantity $\overrightarrow v \times \overrightarrow a $ is constant in time

C) quantity $\overrightarrow v .\overrightarrow a $ is constant in time

D) \overrightarrow F $ arises due to a magnetic field

120

MediumJEE Mains2020

An insect is at the bottom of a hemispherical ditch of radius 1 m. It crawls up the ditch but starts slipping after it is at height h from the bottom. If the coefficient of friction between the ground and the insect is 0.75, then h is : (g = 10 ms–2)

Options:

A) 0.45 m

B) 0.60 m

C) 0.20 m

D) 0.80 m

121

MediumJEE Mains2020

A spaceship in space sweeps stationary interplanetary dust. As a result, its mass increases at a rate ${{dM\left( t \right)} \over {dt}}$ = bv2(t), where v(t) is its instantaneous velocity. The instantaneous acceleration of the satellite is :

Options:

A) -bv3(t)

B) - {{2b{v^3}} \over {M\left( t \right)}}

C) - {{b{v^3}} \over {M\left( t \right)}}

D) - {{b{v^3}} \over {2M\left( t \right)}}

122

MediumJEE Mains2020

A small ball of mass m is thrown upward with velocity u from the ground. The ball experiences a resistive force mkv2 where v is its speed. The maximum height attained by the ball is :

Options:

A) {1 \over k}{\tan ^{ - 1}}{{k{u^2}} \over {2g}}

B) {1 \over {2k}}{\tan ^{ - 1}}{{k{u^2}} \over g}

C) {1 \over {2k}}\ln \left( {1 + {{k{u^2}} \over g}} \right)

D) {1 \over k}\ln \left( {1 + {{k{u^2}} \over {2g}}} \right)

123

MediumJEE Mains2020

A mass of 10 kg is suspended by a rope of length 4 m, from the ceiling. A force F is applied horizontally at the mid point of the rope such that the top half of the rope makes an angle of 45o with the vertical. Then F equal : (Take g = 10 ms–2 and the rope to be massless)

Options:

A) 100 N

B) 75 N

C) 90 N

D) 70 N

124

MediumJEE Mains2019

A spring whose unstretched length is l has a force constant k. The spring is cut into two pieces of unstretched lengths l1 and l2 where, l1 = nl2 and n is an integer. The ratio k1/k2 of the corresponding force constant, k1 and k2 will be :

Options:

A) {1 \over {{n^2}}}

B) {1 \over n}

C) n2

D) n

125

MediumJEE Mains2019

A block of mass 5 kg is (i) pushed in case (A) and (ii) pulled in case (B), by a force F = 20 N, making an angle of 30o with the horizontal, as shown in the figures. The coefficient of friction between the block and floor is $\mu $ = 0.2. The difference between the accelerations of the blocks, in case (B) and case (A) will be : (g = 10 ms–2)

Options:

A) 3.2 ms–2

B) 0.8 ms–2

C) 0 ms–2

D) 0.4 ms–2

126

MediumJEE Mains2019

Two blocks A and B of masses mA = 1 kg and mB = 3 kg are kept on the table as shown in figure. The coefficient of friction between A and B is 0.2 and between B and the surface of the table is also 0.2. The maximum force F that can be applied on B horizontally, so that the block A does not slide over the block B is : [Take g = 10 m/s2]

Options:

A) 8 N

B) 16 N

C) 40 N

D) 12 N

127

MediumJEE Mains2019

A bullet of mass 20 g has an initial speed of 1 ms–1 , just before it starts penetrating a mud wall of thickness 20 cm. If the wall offers a mean resistance of 2.5 × 10–2 N, the speed of the bullet after emerging from the other side of the wall is close to :

Options:

A) 0.3 ms-1

B) 0.1 ms-1

C) 0.7 ms-1

D) 0.4 ms-1

128

MediumJEE Mains2019

A ball is thrown upward with an initial velocity V0 from the surface of the earth. The motion of the ball is affected by a drag force equal to m$\gamma u2 (where m is mass of the ball, u is its instantaneous velocity and \gamma $ is a constant). Time taken by the ball to rise to its zenith is :

Options:

A) {1 \over {\sqrt {\gamma g} }}{\tan ^{ - 1}}\left( {\sqrt {{\gamma \over g}} {V_0}} \right)

B) {1 \over {\sqrt {\gamma g} }}{ln}\left( 1+ {\sqrt {{\gamma \over g}} {V_0}} \right)

C) {1 \over {\sqrt {\gamma g} }}{\sin ^{ - 1}}\left( {\sqrt {{\gamma \over g}} {V_0}} \right)

D) {1 \over {\sqrt {2\gamma g} }}{\tan ^{ - 1}}\left( {\sqrt {{2\gamma \over g}} {V_0}} \right)

129

MediumJEE Mains2019

A block kept on a rough inclined plane, as shown in the figure, remains at rest upto a maximum force 2 N down the inclined plane. The maximum external force up the inclined plane that does not move the block is 10 N. The coefficient of static friction between the block and the plane is : [Take g = 10 m/s2]

Options:

A) {{\sqrt 3 } \over 4}

B) {1 \over 2}

C) {{\sqrt 3 } \over 2}

D) {2 \over 3}

130

MediumJEE Mains2019

Two forces P and Q, of magnitude 2F and 3F, respectively, are at an angle $\theta with each other. If the force Q is doubled, then their resultant also gets doubled. Then, the angle \theta $ is -

Options:

A) 90o

B) 60o

C) 30o

D) 120o

131

MediumJEE Mains2019

A mass of 10 kg is suspended vertically by a rope from the roof. When a horizontal force is applied on the rope at some point. the rope deviated at an angle of 45o at the roof point. If the suspended mass is at equilibrium, the magnitude of the force applied is (g = 10 ms$-$2

Options:

A) 200 N

B) 140 N

C) 70 N

D) 100 N

132

MediumJEE Mains2019

A block of mass 10 kg is kept on a rough inclined plane as shown in the figure. A force of 3 N is applied on the block. The coefficient of static friction between the plane and the block is 0.6. What should be the minimum value of force P, such that the block does not move downward? (take g = 10 ms$-$2)

Options:

A) 32 N

B) 18 N

C) 23 N

D) 25 N

133

MediumJEE Mains2018

Two masses m1 = 5 kg and m2 = 10 kg, connected by an inextensible string over a frictionless pulley, are moving as shown in the figure. The coefficient of friction of horizontal surface is 0.15. The minimum weight m that should be put on top of m2 to stop the motion is :

Options:

A) 10.3 kg

B) 18.3 kg

C) 27.3 kg

D) 43.3 kg

134

MediumJEE Mains2018

A body of mass 2 kg slides down with an acceleration of 3 m/s2 on a rough inclined plane having a slope of ${30^o}$. The external force required to take the same body up the plane with the same acceleration will be : (g = 10 m/s2)

Options:

A) 14 N

B) 20 N

C) 6 N

D) 4 N

135

MediumJEE Mains2018

A given object takes n times more time to slide down a ${45^ \circ } rough inclined plane as it takes to slide down a perfectly smooth {45^ \circ }$ incline. The coefficient of kinetic friction between the object and the incline is :

Options:

A) {1 \over {2 - {n^2}}}

B) 1 - {1 \over {{n^2}}}

C) \sqrt {1 - {1 \over {{n^2}}}}

D) \sqrt {{1 \over {1 - {n^2}}}}

136

MediumJEE Mains2016

A particle of mass m is acted upon by a force F given by the empirical law F =${R \over {{t^2}}}\,v\left( t \right).$ If this law is to be tested experimentally by observing the motion starting from rest, the best way is to plot :

Options:

A) \upsilon $(t) against t2

B) log $\upsilon (t) against {1 \over {{t^2}}}

C) log $\upsilon $(t) against t

D) log $\upsilon (t) against {1 \over {{t}}}

137

MediumJEE Mains2016

A rocket is fired vertically from the earth with an acceleration of 2g, where g is the gravitational acceleration. On an inclined plane inside the rocket, making an angle $\theta with the horizontal, a point object of mass m is kept. The minimum coefficient of friction \mu $min between the mass and the inclined surface such that the mass does not move is :

Options:

A) tan$\theta

B) 2tan$\theta

C) 3tan$\theta

D) tan2$\theta

138

MediumJEE Mains2015

Given in the figure are two blocks $A and B of weight 20 N and 100 N, respectively. These are being pressed against a wall by a force F as shown. If the coefficient of friction between the blocks is 0.1 and between block B and the wall is 0.15, the frictional force applied by the wall on block B$ is :

Options:

A) 120 N

B) 150 N

C) 100 N

D) 80 N

139

MediumJEE Mains2014

A block of mass $m is placed on a surface with a vertical cross section given by y = {{{x^3}} \over 6}. If the coefficient of friction is 0.5,$ the maximum height above the ground at which the block can be placed without slipping is:

Options:

A) {1 \over 6}m

B) {2 \over 3}m

C) {1 \over 3}m

Options:

A) 30 \mathrm{~m} / \mathrm{s}^2

B) 20 \mathrm{~m} / \mathrm{s}^2

C) 40 \mathrm{~m} / \mathrm{s}^2

D) 35 \mathrm{~m} / \mathrm{s}^2

187

MediumMHT CET2025

A mass ' M ' is suspended by a rope from a rigid support at point ' P ' as shown in figure. Another rope is tied at end ' Q ' and pulled horizontally with a force ' F '. If the rope makes an angle ' \theta ' with vertical then the tension in the string ' PQ ' is

Options:

A) F \sin \theta

B) \frac{F}{\sin \theta}

C) F \cos \theta

D) \frac{F}{\cos \theta}

188

MediumMHT CET2025

A machine gun fires a bullet of mass 35 gram with a speed of 600 \mathrm{~m} / \mathrm{s}. The person holding the gun can extract a maximum force of 147 N on it. The number of bullets that can be fired from the gun per second is

Options:

A) 3

B) 5

C) 7

D) 9

189

MediumMHT CET2025

The weight of man in a stationary lift is w_1 and when it is moving downwards with uniform acceleration ' a ' is \mathrm{w}_2. If the ratio \mathrm{w}_1: \mathrm{w}_2=4: 3, then the value of ' a ' is ( \mathrm{g}= acceleration due to gravity)

Options:

A) \frac{\mathrm{g}}{3}

B) \frac{\mathrm{g}}{4}

C) \frac{3}{4} \mathrm{~g}

D) \frac{4}{\mathrm{~g}}

190

MediumMHT CET2025

A constant force acts on two different masses independently and produces accelerations \mathrm{A}_1 and A_2. When the same force acts on their combined mass, the acceleration produced is

Options:

A) \quad A_1-A_2

B) \mathrm{A}_1+\mathrm{A}_2

C) \frac{A_1 A_2}{A_1+A_2}

D) \sqrt{A_1^2+A_2^2}

191

MediumMHT CET2025

A conveyor belt is moving with constant velocity (V). Sand is being dropped on the belt at the rate of \mathrm{M} \mathrm{kg} / \mathrm{s}. The force necessary to keep the belt moving with a constant velocity \mathrm{V} \mathrm{m} / \mathrm{s} will be

Options:

A) \frac{M V}{2} \mathrm{~N}

B) 2 MV N

C) Zero N

D) MV N

192

MediumMHT CET2025

A child stands on a weighing machine inside a lift. When the lift is going down with acceleration \mathrm{g} / 3, the machine shows a reading 20 N . When the lift goes upwards with acceleration \mathrm{g} / 3, the reading would be ( \mathrm{g}= gravitational acceleration)

Options:

A) 40 N

B) 30 N

C) 20 N

D) 50 N

193

MediumMHT CET2025

Which one of the following person is in an inertial frame of reference?

Options:

A) A person (man) in a train which is slowing down to stop.

B) A person (child) revolving in a merry-goround.

C) A person (driver) in a bus which is moving with constant velocity.

D) A person (pilot) in an aeroplane which is taking off.

194

MediumMHT CET2025

Force is applied to a body of mass 3 kg at rest on a frictionless horizontal surface as shown in the force against time (F-t) graph. The speed of the body after 1 s is

Options:

A) 8 \mathrm{~m} / \mathrm{s}

B) 6 \mathrm{~m} / \mathrm{s}

C) 4 \mathrm{~m} / \mathrm{s}

D) 2 \mathrm{~m} / \mathrm{s}

195

MediumMHT CET2024

The pulleys and strings shown in figure are smooth and of negligible mass. For the system to remain in equilibrium, angle \theta should be

Options:

A) \cos ^{-1}(1)

B) \cos ^{-1}\left(\frac{\sqrt{3}}{2}\right)

C) \cos ^{-1}\left(\frac{1}{2}\right)

D) \cos ^{-1}\left(\frac{1}{\sqrt{2}}\right)

196

MediumMHT CET2024

Which one of the following is 'NOT' a contact force?

Options:

A) Force of friction.

B) Normal reaction.

C) Gravitational force.

D) Viscous force.

197

MediumMHT CET2024

Two blocks of masses 6 kg and 4 kg are placed in contact with each other on a smooth surface as shown. If a force of 5 N is applied on a heavier block, the force on the lighter block is

Options:

A) 5N

B) 4N

C) 2N

D) 1N

198

MediumMHT CET2024

The mass of the lift is 200 kg , when it ascends with an acceleration of 4 \mathrm{~m} / \mathrm{s}^2 then the tension in the cable supporting the lift will be [Given: Acceleration due to gravity g=10 \mathrm{~m} / \mathrm{s}^2 ]

Options:

A) 800 N

B) 2800 N

C) 4200 N

D) 2000 N

199

MediumMHT CET2024

Two identical blocks each of mass ' M ' attached to the ends of a massless inextensible string which passes over a pulley with a fixed axis as shown below. A small mass ' m ' is now placed on the block B. The acceleration with which the two blocks move together is [g = gravitational acceleration]

Options:

A) \frac{m g}{2 M+m}

B) \frac{M g}{M+2 m}

C) \frac{\mathrm{Mg}}{2 \mathrm{M}+\mathrm{m}}

D) \frac{m g}{M+2 m}

200

MediumMHT CET2023

A machine gun fires bullets of mass $30 \mathrm{~g} with velocity of 1000 \mathrm{~m} / \mathrm{s}. The man holding the gun can exert a maximum force of 300 \mathrm{~N}$ on it. How many bullets can he fire per second at most?

Options:

A) 3

B) 6

C) 10

D) 9

201

MediumMHT CET2023

A spring balance is attached to the ceiling of a lift. A man hangs his bag on the spring and the spring balance reads $49 \mathrm{~N}, when the lift is stationary. If the lift moves downward with an acceleration of 5 \mathrm{~m} / \mathrm{s}^2, the reading of the spring balance will be \left(g=9.8 \mathrm{~m} / \mathrm{s}^2\right)

Options:

A) 15 N

B) 24 N

C) 49 N

D) 74 N

202

MediumMHT CET2022

A door $1.2 \mathrm{~m} wide requires a force of 1 \mathrm{~N} to be applied perpendicular at the free end to open or close it. The perpendicular force required at a point 0.2 \mathrm{~m}$ distant from the hinges for opening or closing the door is

Options:

A) 3.6 N

B) 2.4 N

C) 1.2 N

D) 6.0 N

203

MediumMHT CET2021

A spring balance is attached to the ceiling of a lift. A man hangs his bag on the spring and the spring balance reads $49 \mathrm{~N}, when the lift is stationary. If the lift moves downward with an acceleration of 5 \mathrm{~m} / \mathrm{s}^2, the reading of the spring balance will be (\mathrm{g}=9.8 \mathrm{~m} / \mathrm{s}^2)

Options:

A) 74 N

B) 15 N

C) 24 N

D) 49 N

204

MediumMHT CET2021

The weight of a man in a lift moving upwards with an acceleration 'a' is 620 N. When the lift moves downwards with the same acceleration, his weight is found to be 340 N. The real weight of the man is

Options:

A) 620 N

B) 680 N

C) 380 N

D) 480 N

205

MediumMHT CET2020

A block of mass $m is moving on rough horizontal surface with momentum p. The coefficient of friction between the block and surface is \mu. The distance covered by block before it stops is [g=$ acceleration due to gravity]

Options:

A) \frac{2 \mu M^2 g}{p^2}

B) \frac{p}{2 \mu M g}

C) \frac{2 \mu M g}{p}

D) \frac{p^2}{2 \mu M^2 g}

206

MediumMHT CET2020

A body of mass $2 \mathrm{~kg} is acted upon by two forces each of magnitude 1 \mathrm{~N} and inclined at 60^{\circ} with each other. The acceleration of the body in \mathrm{m} / \mathrm{s} is [\cos 60^{\circ}=0.5$]

Options:

A) \sqrt{0.75}

B) \sqrt{0.65}

C) \sqrt{0.20}

D) \sqrt{0.35}

207

MediumMHT CET2019

A block of mass M is pulled along a smooth horizontal surface with a rope of mass m by force F. The acceleration of the block will be

Options:

A) \frac{F}{(M-m)}

B) \frac{F}{(M+m)}

C) \frac{F}{m}

D) \frac{F}{M}

208

MediumMHT CET2019

An aircraft is moving with uniform velocity 150 \mathrm{~m} / \mathrm{s} in the space. If all the forces acting on it are balanced, then it will

Options:

A) keep moving with same velocity

B) remain floating at its place

C) escape in space

D) fall down on earth

209

MediumNEET2025

There are two inclined surfaces of equal length (L) and same angle of inclination 45^{\circ} with the horizontal. One of them is rough and the other is perfectly smooth. A given body takes 2 times as much time to slide down on rough surface than on the smooth surface. The coefficient of kinetic friction \left(\mu_k\right) between the object and the rough surface is close to

Options:

A) 0.5

B) 0.75

C) 0.25

D) 0.40

210

MediumNEET2024

A box of mass $5 \mathrm{~kg} is pulled by a cord, up along a frictionless plane inclined at 30^{\circ} with the horizontal. The tension in the cord is 30 \mathrm{~N}. The acceleration of the box is (Take g=10 \mathrm{~m} \mathrm{~s}^{-2}$)

Options:

A) 2 \mathrm{~m} \mathrm{~s}^{-2}

B) Zero

C) 0.1 \mathrm{~m} \mathrm{~s}^{-2}

D) 1 \mathrm{~m} \mathrm{~s}^{-2}

211

MediumNEET2024

A horizontal force $10 \mathrm{~N} is applied to a block A as shown in figure. The mass of blocks A and B are 2 \mathrm{~kg} and 3 \mathrm{kg} respectively. The blocks slide over a frictionless surface. The force exerted by block A on block B$ is :

Options:

A) Zero

B) 4 N

C) 6 N

D) 10 N

212

MediumNEET2024

A particle moving with uniform speed in a circular path maintains:

Options:

A) Constant velocity

B) Constant acceleration

C) Constant velocity but varying acceleration

D) Varying velocity and varying acceleration

213

MediumNEET2023

A block of mass 2 kg is placed on inclined rough surface AC (as shown in figure) of coefficient of friction $\mu. If g = 10 m s^{-2}$, the net force (in N) on the block will be:

Options:

A) 10$\sqrt3

B) zero

C) 10

D) 20

214

MediumNEET2023

A football player is moving southward and suddenly turns eastward with the same speed to avoid an opponent. The force that acts on the player while turning is :

Options:

A) along northward

B) along north-east

C) along south-west

D) along eastward

215

MediumNEET2023

Calculate the maximum acceleration of a moving car so that a body lying on the floor of the car remains stationary. The coefficient of static friction between the body and the floor is 0.15 $\left(g=10 \mathrm{~m} \mathrm{~s}^{-2}\right)$.

Options:

A) 150 \mathrm{~m} \mathrm{~s}^{-2}

B) 1.5 \mathrm{~m} \mathrm{~s}^{-2}

C) 50 \mathrm{~m} \mathrm{~s}^{-2}

D) 1.2 \mathrm{~m} \mathrm{~s}^{-2}

216

MediumNEET2023

A bullet from a gun is fired on a rectangular wooden block with velocity $u. When bullet travels 24 \mathrm{~cm} through the block along its length horizontally, velocity of bullet becomes \frac{u}{3}$. Then it further penetrates into the block in the same direction before coming to rest exactly at the other end of the block. The total length of the block is :

Options:

A) 24 \mathrm{~cm}

B) 28 \mathrm{~cm}

C) 30 \mathrm{~cm}

D) 27 \mathrm{~cm}

217

MediumNEET2022

If $\overrightarrow F = 2\widehat i + \widehat j - \widehat k and \overrightarrow r = 3\widehat i + 2\widehat j - 2\widehat k, then the scalar and vector products of \overrightarrow F and \overrightarrow r $ have the magnitudes respectively as

Options:

A) 10, 2

B) 5, $\sqrt 3

C) 4, $\sqrt 5

D) 10, $\sqrt 2

218

MediumNEET2022

In the diagram shown, the normal reaction force between 2 kg and 1 kg is (Consider the surface, to be smooth) : (Given g = 10 ms$-$2)

Options:

A) 10 N

B) 25 N

C) 39 N

D) 6 N

219

MediumNEET2020

Two bodies of mass 4 kg and 6 kg are tied to the ends of a massless string. The string passes over a pulley which is frictionless (see figure). The acceleration of the system in terms of acceleration due to gravity (g) is :

Options:

A) g/2

B) g/5

C) g/10

D) g

220

MediumNEET2019

A mass m is attached to a thin wire and whirled in a vertical circle. The wire is most likely to break when :

Options:

A) the wire is horizontal

B) inclined at an angle of 60o from vertical

C) the mass is at the lowest point

D) the mass is at the highest point

221

MediumNEET2019

A block of mass 10 kg is in contact against the inner wall of a hollow cylindrical drum of radius 1 m. The coefficient of friction between the block and the inner wall of the cylinder is 0.1. The minimum angular velocity needed for the cylinder to keep the block stationary when the cylinder is vertical and rotating about its axis, will be : (g = 10 m/s2)

Options:

A) {{10} \over {2\pi }}$ rad/s

B) 10 rad/s

C) 10 $\pi $ rad/s

D) \sqrt {10} $ rad/s

222

MediumNEET2018

Which one of the following statements is incorrect?

Options:

A) Rolling friction is smaller than sliding friction.

B) Limiting value of static friction is directly proportional to normal reaction.

C) Frictional force opposes the relative motion.

D) Coefficient of sliding friction has dimensions of length.

223

MediumNEET2018

A block of mass m is placed on a smooth inclined wedge ABC of inclination q as shown in the figure. The wedge is given an acceleration ‘a’ towards the right. The relation between a and q for the block to remain stationary on the wedge is

Options:

A) a = {g \over {\cos ec\theta }}

B) a = {g \over {\cos ec\theta }}

C) a = g\cos \theta

D) a = g\tan \theta

224

MediumNEET2017

One end of string of length $l is connected to a particle of mass 'm' and the other end is connected to a small peg on a smooth horizontal table. If the particle moves in circle with speed '\upsilon $', the net force on the particle (directed towards centre) will be (T represents the tension in the string)

Options:

A) T + {{m{v^2}} \over l}

B) T - {{m{v^2}} \over l}

C) zero

D) T

225

MediumNEET2017

Two blocks A and B of masses 3m and m respectively are connected by a massless and inextensible string. The whole system is suspended by a massless spring as shown in figure. The magnitudes of acceleration of A and B immediately after the string is cut, are respectively

Options:

A) {g \over 3},g

B) g, g

C) {g \over 3},{g \over 3}

D) g,{g \over 3}

226

MediumNEET2016

A car is negotiating a curved road of radius R. The road is banked at an angle $\theta . The coefficient of friction between the tyres of the car and the road is \mu $s. The maximum safe velocity on this road is

Options:

A) \sqrt {{g \over R}{{{\mu _s} + \tan \theta } \over {1 - {\mu _s}\tan \theta }}}

B) \sqrt {{g \over {{R^2}}}{{{\mu _s} + \tan \theta } \over {1 - {\mu _s}\tan \theta }}}

C) \sqrt {g{R^2}{{{\mu _s} + \tan \theta } \over {1 - {\mu _s}\tan \theta }}}

D) \sqrt {gR{{{\mu _s} + \tan \theta } \over {1 - {\mu _s}\tan \theta }}}

227

MediumNEET2015

Two stones of masses m and 2m are whirled in horizontal circles, the heavier one in a radius ${r \over 2}$ and the lighter one in radius r. The tangential speed of lighter stone is n times that of the value of heavier stone when they exprience same centripetal forces. The value of n is

Options:

A) 4

B) 1

C) 2

D) 3

228

MediumNEET2015

A plank with a box on it at one end is gradually raised about the other end. As the angle of inclination with the horizontal reaches 30o, the box starts to slip and slides 4.0 m down the plank in 4.0 s. The coefficients of static and kinetic friction between the box and the plank will be, respectively

Options:

A) 0.5 and 0.6

B) 0.4 and 0.3

C) 0.6 and 0.6

D) 0.6 and 0.5

229

MediumNEET2015

Three blocks A, B and C, of masses 4 kg, 2 kg and 1 kg respectively, are in contact on a frictionless surface, as shown. If a force of 14 N is applied on the 4 kg block, then the contact force between A and B is

Options:

A) 8 N

B) 18 N

C) 2 N

D) 6 N

230

MediumNEET2015

A block A of mass m1 rests on a horizontal table. A light string connected to it passes over a frictionless pully at the edge of table and from its other end another block B of mass m2 is suspended. The coefficient of kinetic friction between the block and the table is $\mu $k. When the block A is sliding on the table, the tension in the string is

Options:

A) {{{m_1}{m_2}(1 + {\mu _k})g} \over {({m_1} + {m_2})}}

B) {{{m_1}{m_2}(1 - {\mu _k})g} \over {({m_1} + {m_2})}}

C) {{\left( {{m_2} + {\mu _k}{m_1}} \right)g} \over {\left( {{m_1} + {m_2}} \right)}}

D) {{\left( {{m_2} - {\mu _k}{m_1}} \right)g} \over {\left( {{m_1} + {m_2}} \right)}}

231

MediumNEET2014

A system consists of three masses m1, m2 and m3 connected by a string passing over a pulley P. The mass m1 hangs freely and m2 and m3 are on a rough horizontal table (the coefficient of friction = $\mu $). The pulley is frictionless and of negligible mass. The downward acceleration of mass m1 is (Assume m1 = m2 = m3 = m)

Options:

A) {{g\left( {1 - g\mu } \right)} \over 9}

B) {{2g\mu } \over 3}

C) {{g\left( {1 - 2\mu } \right)} \over 3}

D) {{g\left( {1 - 2\mu } \right)} \over 2}

232

MediumNEET2014

A balloon with mass m is descending down with an acceleration a (where a < g). How much mass should be removed from it so that it starts moving up with an acceleration a ?

Options:

A) {{2ma} \over {g + a}}

B) {{2ma} \over {g - a}}

C) {{ma} \over {g + a}}

D) {{ma} \over {g - a}}

233

MediumNEET2013

A car is moving in a circular horizontal track of radius 10 m with a constant speed of 10 m/s. A bob is suspended from the roof of the car by a light wire of length 1.0 m. The angle made by the wire with the vertical is

Options:

A) {\pi \over 3}

B) {\pi \over 6}

C) {\pi \over 4}

D) 0o

234

MediumNEET2013

Three blocks with masses m, 2m and 3m are connected by strings, as shown in the figure. After an upward force F is applied on block m, the masses move upwards at constant speed v. What is the net force on the block of mass 2m ? (g is the acceleration due to gravity)

Options:

A) 3mg

B) 6mg

C) zero

D) 2mg

235

MediumNEET2013

The upper half of an inclined plane of inclination $\theta $ is perfectly smooth while lower half is rough. A block starting from rest at the top of the plane will again come to rest at the bottom, if the coefficient of friction between the block and lower half of the plane is given by

Options:

A) \mu = 2 tan\theta

B) \mu = tan\theta

C) \mu = {1 \over {\tan \theta }}

D) \mu = {2 \over {\tan \theta }}

236

MediumNEET2012

A stone is dropped from a height h. It hits the ground with a certain momentum P. If the same stone is dropped from a height 100% more than the previous height, the momentum when it hits the ground will change by

Options:

A) 68%

B) 41%

C) 200%

D) 100%

237

MediumNEET2011

A conveyor belt is moving at a constant speed of 2 ms$-1. A box is gently dropped on it. The coefficient of friction between them is \mu = 0.5. The distance that the box will move relativce to belt before coming to rest on it, taking g = 10 m s-$2,, is

Options:

A) 0.4 m

B) 1.2 m

C) 0.6 m

D) zero

238

MediumNEET2011

A body of mass M hits normally a rigid wall with velocity V and bounces back with the same velocity. The impulse experienced by the body is

Options:

A) MV

B) 1.5 MV

C) 2MV

D) zero

239

MediumNEET2011

A person of mass 60 kg is inside a lift of mass 940 kg and presses the button on control panel. The lift starts moving upwards with an acceleration 1.0 m/s2. If g = 10 ms$-$2, the tension in the supporting cable is

Options:

A) 8600 N

B) 9680 N

C) 11000 N

D) 1200 N

240

MediumNEET2010

A block of mass m is in contact with the cart C as shown in the figure. The coefficient of static friction between the block and the cart is $\mu . The acceleration \alpha $ of the cart that will prevent the block from falling satisfies

Options:

A) \alpha > {{mg} \over \mu }

B) \alpha > {g \over {\mu m}}

C) \alpha \ge {g \over \mu }

D) \alpha < {g \over \mu }

241

MediumNEET2009

The mass of a lift is 2000 kg. When the tension in the supporting cable is 28000 N, then its acceleration is :

Options:

A) 4 m s$-$2 upwards

B) 4 m s$-$2 downwards

C) 14 m s$-$2 upwards

D) 30 m s$-$2 downwards

242

MediumNEET2009

A body, under the action of a force $\overrightarrow F = 6\widehat i - 8\widehat j + 10\widehat k,$ acquires an accelerations of 1 m/s2. The mass of this body must be

Options:

A) 10 kg

B) 20 kg

C) 10$\sqrt 2 $ kg

D) 2$\sqrt {10} $ kg

243

MediumNEET2008

Three forces acting on a body are shown in the figure. To have the resultant force only along the y-direction, the magnitude of the minimum additional force needed is

Options:

A) {{\sqrt 3 } \over 4}N

B) {\sqrt 3 }$ N

C) 0.5 N

D) 1.5 N

244

MediumNEET2008

A roller coaster is designed such that riders experience ''weightlessness'' as they go round the top of a hill whose radius of curvature is 20 m. The speed of the car at the top of the hill is between

Options:

A) 16 m/s and 17 m/s

B) 13 m/s and 14 m/s

C) 14 m/s and 15 m/s

D) 15 m/s and 16 m/s

245

MediumNEET2008

Sand is being dropped on a conveyer belt at the rate of M kg/s. The force necessary to keep the belt moving with a constant velocity of $\upsilon $ m/s will be :

Options:

A) {{Mv} \over 2}$ newton

B) zero

C) M$v$ newton

D) 2 M$v$ newton

246

MediumNEET2007

A block B is pushed momentarily along a horizontaly surface with an initial velocity V. If $\mu $ is the coefficient of sliding friction between B and the surface, block B will come to rest after a time

Options:

A) g$\mu $/V

B) g/V

C) V/g

D) V/(g$\mu $).

247

MediumNEET2004

A block of mass m is placed on a smooth wedge of inclination $\theta $. The whole system is accelerated horizontally so that the block does not slip on the wedge. The force exerted by the wedge on the block will be (g is acceleration due to gravity)

Options:

A) mg cos$\theta

B) mg sin$\theta

C) mg

D) mg/cos $\theta

248

MediumNEET2004

The coefficient of static friction, $\mu $s, between block A of mass 2 kg and the table as shown in the figure is 0.2. What would be the maximum mass value of block B so that the two blocks do not move? The string and the pulley are assumed to be smooth and massless. (g = 10 m/s2)

Options:

A) 2.0 kg

B) 4.0 kg

C) 0.2 kg

D) 0.4 kg

249

MediumNEET2003

A monkey of mass 20 kg is holding a vertical rope. The rope will not break when a mass of 25 kg is suspended from it but will break if the mass exceeds 25 kg. What is the maximum acceleration with which the monkey can climb up along the rope ? (g = 10 m/s2)

Options:

A) 5 m/s2

B) 10 m/s2

C) 25 m/s2

D) 2.5 m/s2

250

MediumNEET2003

A man weight 80 kg. He stands on a weighting scale in a lift which is moving upwards with a uniform acceleration of 5 m/s2. What would be the reading on the scale ? (g = 10 m/s2)

Options:

A) zero

B) 400 N

C) 800 N

D) 1200 N

251

MediumNEET2002

A block of mass 10 kg placed on rough horizontal surface having coefficient of friction m = 0.5, if a horizontal force of 100 N acting on it then acceleration of the block will be

Options:

A) 10 m/s2

B) 5 m/s2

C) 15 m/s2

D) 0.5 m/s2.

252

MediumNEET2002

An object of mass 3 kg is at rest. Now a force of $\overrightarrow F = 6t2 \widehat i + 4t \widehat j$ is applied on the object then velocity of object at t = 3 sec. is

Options:

A) 18$\widehat i + 3\widehat j

B) 18$\widehat i + 6\widehat j

C) 3$\widehat i + 18\widehat j

D) 18$\widehat i + 4\widehat j

253

MediumNEET2002

A lift of mass 1000 kg which is moving with acceleration of 1 m/s2 in upward direction, then the tension developed in string which is connected to lift is

Options:

A) 9800 N

B) 10,800 N

C) 11,000 N

D) 10,000 N.

254

MediumNEET2001

On the horizontal surface of a truck a block of mass 1 kg is placed (m = 0.6) and truck is moving with acceleration 5 m/sec2 then the frictional force on the block will be

Options:

A) 5 N

B) 6 N

C) 5.88 N

D) 8 N

255

MediumNEET2001

A cricketer catches a ball of mass 150 gm in 0.1 sec moving with speed 20 m/s, then he experiences force of

Options:

A) 300 N

B) 30 N

C) 3 N

D) 0.3 N.

256

MediumNEET2001

A 1 kg stationary bomb is exploted in three parts having mass 1 : 1 : 3 respectively. Parts having same mass move in perpendicular direction with velocity 30 m/s, then the velocity of bigger part will be

Options:

A) 10\sqrt 2 $ m/sec

B) {{10} \over {\sqrt 2 }}$ m/sec

C) 15\sqrt 2 $ m/sec

D) {{15} \over {\sqrt 2 }}$ m/sec

257

MediumNEET2001

250 N force is required to raise 75 kg mass from a pulley. If rope is pulled 12 m then the load is lifted to 3 m. the efficiency of pulley system will be

Options:

A) 25%

B) 33.3%

C) 75%

D) 90%

258

MediumNEET2000

Two masses as shown in the figure are suspended from a massless pulley. The acceleration of the system when masses are left free is

Options:

A) {{2g} \over 3}

B) {g \over 3}

C) {g \over 9}

D) {g \over 7}$.

259

MediumNEET2000

A body of mass 3 kg hits a wall at an angle of 60o and returns at the same angle. The impact time was 0.2 sec. The force exerted on the wall

Options:

A) 150${\sqrt 3 }$ N

B) 50${\sqrt 3 }$ N

C) 100 N

D) 75${\sqrt 3 }$ N.

260

MediumVITEEE2024

A disc of mass 10 g is kept floating horizontally by throwing 10 marbles per second against it from below. If the mass of each marble is 5 g . What will be velocity with which the marble are striking the disc? Assume that, the marble strikes the disc normally and rebound downwards with the same speed.

Options:

A) 2.98 \mathrm{~m} / \mathrm{s}

B) 0.98 \mathrm{~m} / \mathrm{s}

C) 0.49 \mathrm{~m} / \mathrm{s}

D) 1.96 \mathrm{~m} / \mathrm{s}

261

MediumVITEEE2023

Three blocks of masses $m_1, m_2 and m_3 are connected by massless strings, as shown, on a frictionless table. They are pulled with a force, T_3=40 \mathrm{~N}. If m_1=10 \mathrm{~kg}, m_2=8 \mathrm{~kg} and m_3=2 \mathrm{~kg}, the tension T_2$ will be

Options:

A) 20 N

B) 40 N

C) 24 N

D) 36 N

262

MediumVITEEE2022

The system is pushed by a force $F as shown in figure. All surfaces are smooth except between B and C. Friction coefficient between B and C is \mu. Minimum value of F to prevent block B$ from downward slipping is

Options:

A) \left(\frac{3}{2 \mu}\right) m g

B) \left(\frac{5}{2 \mu}\right) m g

C) \left(\frac{5}{2}\right) \mu m g

D) \left(\frac{3}{2}\right) \mu m g

262

Total Questions

Easy

209

Medium

Hard

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