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In elastic collision, 100% energy transfer takes place when 

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Important Questions on Laws of Motion

HARD
A simple pendulum, made of a string of length l and a bob of mass m, is released from a small angle θ0. It strikes a block of mass M, kept on horizontal surface at its lowest point of oscillations, elastically. It bounces back and goes up to an angle θ1. Then M is given by:
HARD

A sphere of mass m moving with velocity v collides head-on another sphere of same mass which is at rest. The ratio of final velocity of the second sphere to the initial velocity of the first sphere is  (e is the coefficient of restitution and collision is inelastic)

HARD
An alpha- particle of mass m suffers 1- dimensional elastic collision with a nucleus at rest of unknown mass. It is scattered directly backwards losing 64% of its initial kinetic energy. The mass of the nucleus is
MEDIUM

This question has Statement - I and Statement - II  of the four choices given after the Statements, choose the one that best describes the two Statements.

Statement - I: A point particle of mass m moving with speed ν collides with stationary point particle of mass M. If the maximum energy loss possible is given as
f12mν2 then f=mM+m.

Statement - II: Maximum energy loss occurs when the particles get stuck together as a result of the collision.

HARD
Two particles A and B of equal mass M are moving with the same speed v as shown in figure. They collide completely inelastic and move as a single particle C. The angle θ that the path of C makes with the X-axis is given by-

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EASY
On a frictionless surfaces, a block of mass M moving at speed v collides elastically with another block of same mass M which is initially at rest. After collision the first block moves at an angle θ to its initial direction and has a speed v3 . The second block's speed after the collision is:
HARD
Three blocks A, B and C are lying on a smooth horizontal surface, as shown in the figure. A and B have equal masses m while C has mass M. Block A is given an initial speed v towards B due to which it collides with B perfectly inelastically. The combined mass collides with C, also perfectly inelastically. 56th of the initial kinetic energy is lost in the whole process. What is the value of M/m?
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HARD
An object is dropped from a height h from the ground. Every time it hits the ground it loses 50% of its kinetic energy. The total distance covered as t is:
HARD
In a collinear collision, a particle with an initial speed v0 strikes a stationary particle of the same mass. If the final total kinetic energy is 50% greater than the original kinetic energy, the magnitude of the relative velocity between the two particles, after the collision, is
MEDIUM
A moving block having mass m, collides with another stationary block having mass 4m. The lighter block comes to rest after collision. When the initial velocity of the lighter block is v, then the value of coefficient of restitution (e) will be
HARD

A block of mass m=10 kg rests on a horizontal table. The coefficient of friction between the block and the table is 0.05. When hit by a bullet of mass 50 g moving with speed v, that gets embedded in it, the block moves and comes to stop after moving a distance of 2 m on the table. If a freely falling object were to acquire speed v10 after being dropped from height H, then neglecting energy losses and taking g=10 m s-2, the value of H is close to

 

MEDIUM
A satellite of mass M is in a circular orbit of radius R about the center of the earth. A meteorite of the same mass, falling towards the earth, collides with the satellite completely inelastic. The speeds of the satellite and the meteorite are the same, just before the collision. The subsequent motion of the combined body will be:
HARD

A large number (n) of identical beads, each of mass m and radius r are strung on a thin smooth rigid horizontal rod of length L(Lr) and are at rest at random positions. The rod is mounted between two rigid supports (see figure). If one of the beads is now given a speed v, the average force experienced by each support after a long time is (assume all collisions are elastic):
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EASY
A ball is thrown vertically downwards from a height of 20 m with an initial velocity v0. It collides with the ground, loses 50 percent of its energy in collision and rebounds to the same height. The initial velocity v0 is: (Take g=10 s-2)
HARD
An oscillator of mass M is at rest in its equilibrium position in a potential, V=12kx X2 . A particle of mass m comes from the right with speed u and collides completely inelastic with M and sticks to it. This process repeats every time the oscillator crosses its equilibrium position. The amplitude of oscillations after 13 collisions is: M=10, m=5, u=1, k=1
HARD
A tennis ball is dropped on a horizontal smooth surface. It bounces back to its original position after hitting the surface. The force on the ball during the collision is proportional to the length of compression of the ball. Which one of the following sketches describes the variation of its kinetic energy K with  t time most appropriately? The figures are only illustrative and not to the scale.
HARD
It is found that if a neutron suffers an elastic collinear collision with a deuterium at rest, the fractional loss of its energy is Pd, while for its similar collision with a carbon nucleus at rest, the fractional loss of energy is Pc. The values of Pd and Pc are respectively
MEDIUM
A smooth sphere of mass M moving with velocity u directly collides elastically with another sphere of mass m at rest. After the collision, their final velocities are V and v respectively. Then v is
EASY
Two identical balls A and B having velocities of 0.5 m s-1 and -0.3 m s-1, respectively, collide elastically in one dimension. The velocities of B and A after the collision, respectively, will be
MEDIUM
A particle of mass m moving in the x direction with speed 2v is hit by another particle of mass 2m moving in the y direction with speed v. If the collision is perfectly inelastic, the percentage loss in the energy during the collision is close to: