Linear Momentum of a System of Particles

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Linear Momentum of a System of Particles: Overview

In this topic, we will learn concept of linear momentum of a system of particles. It also explains how it is related to the centre of mass and motion of the centre of mass.

Important Questions on Linear Momentum of a System of Particles

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A body of mass 5 kg explodes at rest into three fragments with masses in the ratio 1 : 1 : 3. The fragment with equal masses fly in mutually perpendicular directions with speeds of 21 ms-1​. The velocity of heaviest fragment in ms-1 will be

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A shell is fired from a canon, it explodes in mid air, its total :

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Three particles A, B and C of equal mass move with equal speed v along the medians of an equilateral triangle as shown in figure. They collide at the centroid G of the triangle. After the collision, A comes to rest, B retraces its path with the speed V. What is the velocity of C?

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A nucleus disintegrates into two nuclear parts which have their velocities in the ratio 2:1. The ratio of their nuclear sizes will be

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A man throws a ball straight up. The ball has a momentum in the vertically upward direction.The principle of conservation of momentum demands that the earth has

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Two balls having linear momenta p1=pi^ and p2=-pi^, undergo a collision in free space. There is no external force acting on the balls. Let p1' and p2' be their final momenta. The following option (s) is (are) not allowed for any non-zero value of p, a1, a2, b1, b2, c1 and c2.

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A man of mass 50 kg is standing at one end of a boat of length 25 m and mass 200 kg. He starts running and when he reaches the other end, he has a velocity 2 ms-1 with respect to the boat. The final velocity of the boat is (in ms-1)

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A shell of mass 10 kg is moving with a velocity of 10 m s-1 when it blasts and forms two parts of mass 9 kg and 1 kg respectively. If the 1st mass is stationary, the velocity of the 2nd is

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A ball of mass 0.2 kg rests on a vertical post of height 5 m. A bullet of mass 0.01 kg, travelling with a velocity v m/s in a horizontal direction, hits the centre of the ball. After the collision, the ball and bullet travel independently. The ball hits the ground at a distance of 20 m and the bullet at a distance of 100 m from the foot of the post. The initial velocity v of the bullet is

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A shell is fired from a cannon with a velocity v m s-1  at an angle θ with the horizontal direction. At the highest point in its path it explodes into two pieces of equal mass. One of the pieces retraces its path to the cannon with speed v cosθ then the speed (in m  s-1) of the other piece immediately after the explosion is

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A 3 kg ball strikes a heavy rigid wall with a speed of 10 m/s at an angle of 60° with the wall. It gets reflected with the same speed at 60° as shown in Fig.If the ball is in contact with the wall for 0.2 s, the average force on the ball by the wall is:

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A stationary body explodes into four identical fragments such that three of them fly off mutually perpendicular to each other, each with a kinetic energy E02 . The total energy of explosion is

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A bullet of mass m moving with velocity v is fired into a wooden block of mass M. If the bullet remains embedded in the block, the final velocity of the system is

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The momentum of a body is increased by 25%. The kinetic energy is increased by about 56%.

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In the non-relativistic regime, if the momentum is increased by 100%, the percentage increase in kinetic energy is (in %)

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A gun fires a shell and recoils horizontally. If the shell travels along the barrel with speed v, then what is the ratio of speed with which the gun recoils if (i) the barrel is horizontal (ii) inclined at an angle of 30° with horizontal?

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Three balls A, B and C mA=mC=4mB are placed on a smooth horizontal surface. The ball B collides with the ball C with an initial velocity ν as shown in the figure. The total number of collisions between the balls will be (all collisions are elastic),

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A ball of mass 0.2 kg rests on a vertical post of height 5 m. A bullet of mass 0.01 kg, traveling with a velocity ν m/s in a horizontal direction, hits the centre of the ball. After the collision, the ball and bullet travel independently. The ball hits the ground at a distance of 20 m and the bullet at a distance of 100 m from the foot of the post. The initial velocity ν of the bullet is

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Find the speed of the daughter nucleus when a nucleus of X22084 originally at rest emits an α-particle with speed v0.

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A cart is initially at rest and may roll freely. A 10 kg package drops into a 25 kg cart with a velocity of 3 m/s. Determine  (a) the final velocity of the cart, (b) the impulse exerted by the cart on the package, (c) the fraction of the initial energy lost in the impact.