Free NEET Physics multiple-choice questions on Collisions (1D and 2D). Attempt each question and reveal the answer with a full explanation.
A mass m is moving with velocity v and collides elastically with another mass m moving with velocity -v (opposite direction). Their velocities after collision are: -v and v v and -v 0 and 0 2v and -2v A ball is dropped from a height h on a floor. If the coefficient of restitution is e , the height to which the ball first rebounds is: e 2 h eh e 4 h h/e 2 Two identical balls A and B collide head-on elastically. If A is moving with 4 m/s and B is moving with -2 m/s, their velocities after collision are: -2 m/s and 4 m/s 4 m/s and -2 m/s -4 m/s and 2 m/s 0 m/s and 2 m/s A small sphere of mass m is dropped from a height h . It rebounds to a height h/4 . The coefficient of restitution is: 1/2 1/4 1/16 1/ 2 A bullet of mass a and velocity b is fired into a large block of mass c . The final velocity of the system is: ab a+c ab c (a+c)b a ac a+b A ball of mass m hits a floor with speed v and rebounds with speed v/2 . The coefficient of restitution is: 0.5 0.25 1.0 0.75 A body of mass m moving with velocity v collides head-on elastically with another body of mass m at rest. After the collision, the velocities of the two bodies are: 0 and v v and 0 v/2 and v/2 -v and v Two bodies with kinetic energies in the ratio 4:1 are moving with equal linear momentum. The ratio of their masses is: 1:4 4:1 1:2 1:16 A ball of mass m is moving with velocity v . It hits a wall and rebounds with the same velocity. If the coefficient of restitution is e , then e is: 1 0 0.5 Infinite In a perfectly inelastic collision, which of the following is conserved? Linear momentum only Kinetic energy only Both linear momentum and kinetic energy Neither linear momentum nor kinetic energy A ball of mass m is dropped from a height h . It rebounds to a height h 1 . The coefficient of restitution e is given by: h 1 / h h 1 / h (h 1 / h) 2 h / h 1 A heavy ball is moving with velocity v and collides elastically with a very light ball at rest. The velocity of the light ball after collision is approximately: 2v v v/2 Zero A body of mass 2 kg is moving with speed v such that its kinetic energy is 100 J. If it collides elastically with an identical body at rest, the speed of the second body after collision is: 10 m/s 5 m/s 20 m/s 0 m/s Two bodies of mass 1 kg and 4 kg are moving with equal kinetic energies. The ratio of the magnitudes of their linear momenta is: 1 : 2 1 : 4 4 : 1 1 : 16 The coefficient of restitution e for a perfectly inelastic collision is: 0 1 0.5 Infinity Which of the following remains conserved in an oblique perfectly elastic collision? Linear momentum and Kinetic energy Only Linear momentum Only Kinetic energy Angular momentum only The coefficient of restitution e for a perfectly elastic collision is: 1 0 0.5 Infinite The coefficient of restitution e for a collision is 0.5 . If the relative velocity of approach is 10 m/s , the relative velocity of separation will be: 5 m/s 20 m/s 10 m/s 0 m/s A bullet of mass 10 g is fired from a gun of mass 2 kg with a velocity of 200 m/s. The kinetic energy of the gun is: 1 J 2 J 0.5 J 4 J A particle of mass m 1 is moving with a velocity v and collides elastically with a particle of mass m 2 at rest. After the collision, the particles move with velocities v/3 and v 2 respectively. The ratio m 1/m 2 is: 0.5 1 2 1.5 A mass m is moving with speed 2v and collides with another identical mass m moving with speed v in the same direction. If the collision is perfectly inelastic, the loss in kinetic energy is: 1 4 mv 2 1 2 mv 2 3 4 mv 2 mv 2 A body of mass m moving with velocity v makes a head-on elastic collision with another body of mass 2m which is initially at rest. The fraction of kinetic energy lost by the colliding body (mass m ) is: 8/9 4/9 1/9 5/9 An elastic ball is dropped from a height h . It collides with the floor and rebounds. If 10 % of its mechanical energy is lost in the collision, the height to which it rebounds is: 0.9h 0.1h 0.9 h 0.81h A metal ball of mass 2 kg moving with speed of 36 km/h has a head-on collision with a stationary ball of mass 3 kg . If after collision, both the balls move as a single mass, then the loss in kinetic energy due to collision is: 60 J 100 J 40 J 80 J A mass m moving with speed v in the x-direction collides with another mass M at rest. If m sticks to M , the fraction of energy lost in the collision is: M/(M+m) m/(M+m) M/m m/M A body of mass m hits a wall with speed v at an angle of 30 with the normal and reflects back with the same speed at the same angle. The magnitude of the impulse imparted to the wall is: 2mv 30 mv 30 2mv 30 mv A body of mass M moves horizontally with speed v and collides with another body of mass M moving vertically upward with speed v . They stick together after collision. The speed of the combined mass is: v/ 2 v/2 2 v v A stationary particle explodes into two particles of masses m 1 and m 2 which move in opposite directions with velocities v 1 and v 2 . The ratio of their kinetic energies E 1/E 2 is: m 2/m 1 m 1/m 2 (m 2/m 1) 2 1 A ball of mass m moving with speed u collides elastically with another ball of mass m at rest. If the collision is oblique, the angle between their velocities after collision is: 90 0 45 180 A body of mass 4 kg is moving with speed 5 m/s. It collides elastically with another body of mass 2 kg moving with speed 2 m/s in the same direction. The relative velocity of separation after collision is: 3 m/s 7 m/s 1 m/s 5 m/s A body of mass m moving with velocity 3 km/h collides with a body of mass 2m at rest and sticks to it. The fraction of the initial kinetic energy lost in the collision is: 2/3 1/3 1/2 1/4 A block of mass m is moving with a speed v on a smooth horizontal surface. It strikes another mass 2m at rest and they stick together. The fraction of kinetic energy lost is: 2/3 1/3 1/2 1/4 A shell of mass 5m at rest explodes into three fragments. Two fragments, each of mass m , fly off in mutually perpendicular directions with speed v . The kinetic energy exerted by the third fragment is: mv 2 / 3 3mv 2 / 2 mv 2 4mv 2 / 3 Two identical spheres A and B collide. Sphere A has velocity v and B is at rest. The collision is NOT head-on. After the elastic collision, the angle between the velocities of the two spheres is: 90 45 180 0 A block of mass M is moving with a velocity v on a smooth horizontal surface. It collides with another block of mass M at rest and they stick together. The ratio of final kinetic energy to initial kinetic energy is: 1 : 2 1 : 1 2 : 1 1 : 4 A ball of mass m moving with speed v makes a head-on collision with an identical ball at rest. The coefficient of restitution is e . The ratio of velocities after collision v 1 / v 2 is: (1-e) / (1+e) (1+e) / (1-e) e 1/e Two identical bodies A and B collide. A is moving with velocity v and B is at rest. If the collision is NOT elastic, then after collision: Velocity of A must be less than v/2 if they stick together Velocity of B must be v Total kinetic energy is conserved The bodies must always stick together A body of mass M is moving with a constant velocity v on a smooth horizontal surface. It collides with another body of mass m at rest. For the maximum transfer of kinetic energy from M to m , the ratio M/m should be: 1 0.5 2 Infinity A bullet of mass m moving with velocity v strikes a suspended wooden block of mass M . If the block rises to a height h , the initial velocity v of the bullet is: M+m m 2gh 2gh m M+m 2gh M+m M 2gh A ball of mass m hits a floor with speed v and rebounds. If the coefficient of restitution is e , the change in momentum of the ball is: mv(1+e) mv(1-e) mve 2mve In a perfectly elastic collision between two identical particles, one of which is at rest, the angle between their velocities after the collision (if the collision is not head-on) is: 90 45 0 180 A bullet of mass m moving with velocity v strikes a suspended wooden block of mass M and stays inside. If the block rises to a height h , the initial velocity of the bullet v is: M+m m 2gh 2gh m M+m 2gh M m 2gh A ball of mass m hits a floor with speed v at an angle of 30 with the normal. If the collision is perfectly elastic, the change in momentum of the ball is: 2mv 30 2mv 30 mv 30 Zero A particle of mass m 1 moving with velocity v collides with a mass m 2 at rest. If they stick together, the loss in kinetic energy is: m 1 m 2 2(m 1 + m 2) v 2 m 1 m 2 (m 1 + m 2) v 2 m 1 2 2(m 1 + m 2) v 2 m 2 2 2(m 1 + m 2) v 2 A body of mass M moving with speed u collides head-on elastically with a body of mass m at rest. If M >> m , the speed of the body of mass m after collision is approximately: 2u u zero u/2 A body of mass M moving with speed u hits another body of mass m at rest elastically and head-on. The fraction of energy retained by the incoming body M is: ( M-m M+m ) 2 ( 2M M+m ) 2 4Mm (M+m) 2 M-m M+m In an elastic oblique collision of two identical particles, one of which is at rest, the angle between their velocities after collision is: 90 0 45 180 A bullet of mass m moving with velocity v strikes a suspended wooden block of mass M and gets embedded. The loss in kinetic energy of the system is: Mm v 2 2(M+m) m 2 v 2 2(M+m) M v 2 2 m v 2 2 A body of mass m is moving with a velocity v . It collides with another body of the same mass m moving with velocity v in a direction perpendicular to the first. If the collision is perfectly inelastic, the speed of the composite body will be: v/ 2 2 v v/2 2v Two masses m 1 and m 2 are connected by a spring. They are pulled apart and then released. The ratio of their maximum kinetic energies K 1/K 2 is: m 2/m 1 m 1/m 2 m 2/m 1 (m 2/m 1) 2 A sphere of mass m moving with velocity u hits another identical sphere at rest. If the collision is head-on and the coefficient of restitution is e , the ratio of velocities of the two spheres after collision is: (1-e)/(1+e) (1+e)/(1-e) e/(1+e) (1-e)/e An explosion breaks a rock into three parts in a horizontal plane. Two of them go off at right angles to each other. The first part of mass 1 kg moves with a speed of 12 m/s and the second part of mass 2 kg moves with 8 m/s speed. If the third part flies off with 4 m/s speed, then its mass is: 5 kg 3 kg 7 kg 17 kg A block of mass M is attached to a spring of spring constant k and is resting on a smooth horizontal surface. A bullet of mass m moving with velocity v strikes the block and gets embedded in it. The maximum compression of the spring is: v m 2 k(M+m) v m k v M+m k v m 2 kM A bullet of mass m and velocity v is fired into a block of mass M suspended by a string. The bullet gets embedded in the block. The height to which the system rises is: (m 2 v 2) / [2g(M+m) 2] (mv 2) / [2g(M+m)] v 2/2g m v 2 / 2Mg A shell of mass m is at rest. It explodes into three fragments of masses in the ratio 2:2:1 . The fragments having equal masses fly off in mutually perpendicular directions with speed v . The speed of the third fragment is: 2 2 v 2v 2 v 3 2 v A body of mass M hits a wall normally with velocity v and bounces back elastically. The change in kinetic energy of the body is: Zero Mv 2 1/2 Mv 2 -Mv 2 A force F = i + 3 j + 6 k is acting at a point r = 2 i - 6 j - 12 k . The value of for which angular momentum about origin is conserved is: -1 1 2 0 A mass m moving with speed v collides with another mass 2m at rest. If the collision is perfectly elastic and head-on, the fraction of energy retained by the colliding mass m is: 1/9 8/9 1/3 4/9 A mass m moving with speed u collides with another mass M at rest. If the collision is head-on and m stops after the collision, the coefficient of restitution e is: m/M M/m 1 0 A ball is dropped from a height h . If e is the coefficient of restitution, the total distance traveled by the ball before it comes to rest is: h( 1+e 2 1-e 2 ) h( 1-e 2 1+e 2 ) h( 1+e 1-e ) h( 1-e 1+e ) A ball is dropped from a height h on a floor. If the coefficient of restitution is e , the total distance covered by the ball before it comes to rest is: h ( 1+e 2 1-e 2 ) h ( 1-e 2 1+e 2 ) h ( 1+e 1-e ) h ( 1-e 1+e ) A bullet of mass m is fired into a large block of wood of mass M suspended by a light inextensible string of length L . The bullet gets embedded in the block and the combination rises to a height h . The initial kinetic energy of the bullet was: (M+m) 2 m gh (M+m)gh M+m m gh m 2 M+m gh A ball of mass m falls from a height h on a floor for which the coefficient of restitution is e . The total time elapsed before the ball comes to rest is: 2h g ( 1+e 1-e ) 2h g ( 1-e 1+e ) 2h g ( 1+e 2 1-e 2 ) 2h g e 1-e Bob B of mass m at rest is hanging vertically from the ceiling via a massless string of length 10 m, as shown in the figure. Point mass A of mass m travelling horizontally with speed 10 ms -1 hits bob B elastically. The bob B rises h meter after the collision. Taking the acceleration due to gravity g=10 ms -2 and neglecting the size of the bob, the value of h is: 8 7 5 2.5 A ball is dropped from a height H . It rebounds from the floor to a height h < H . The coefficient of restitution e is: h/H h/H (h/H) 2 H/h Two masses 1 g and 9 g are moving with equal kinetic energies. The ratio of the magnitudes of their linear momenta is: 1:3 1:9 3:1 9:1 Which of the following remains constant during an inelastic collision between two bodies? Total linear momentum Total kinetic energy Velocity of each body Total mechanical energy