# 23 - Centre of mass and momentum conservation Questions Answers

A flywheel rotating at the rate of 100 rpm slows down at a constant rate of 2 rad s–2. Calculate the time it will take to stop and the rotation it will make before coming to rest.

**Asked By: RAJNI SINGH**1 year ago

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**submit your answer**a body of mass 3m travelling due east with a speed 2u collides with a body of mass 2m with a speed of u .show that the speed after collision of body mass 2m = 1/5(9e + 4)u when the coefficient of restitution is e

**Asked By: ANTHONY CHOTO**3 year ago

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a 20g bullet pierces through a plate of mass 1kg and then comes to rest in a second plate of mass 2.98kg. the two plates initially at rest now move with equal velocity. find % loss of initial velocity of bullet when it is b/w the llates. any loss of material due to piercing may be neglected .

**Asked By: VAISHNAVI RAJPUT**3 year ago

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**submit your answer**two particles of masses 4kg and 6 kg are at rest separated by 20m. if they move towards each other due to mutual force of attraction the position of the point where they meet is

**Asked By: RAGHINI RAVI MAVUDOORI**3 year ago

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a particle of mass m dropped from a height strikes ground with coefficient of restitution e find average force over the time till which it come to rest..(total time for rest as calculated is [{√(2h/g)}.{(1+e)/(1-e)}]

**Asked By: HARSHUL GUPTA**4 year ago

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a particle of mass m dropped from a height strikes ground with coefficient of restitution e find average force over the time

**Asked By: HARSHUL GUPTA**4 year ago

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**submit your answer****Asked By: NISAR**4 year ago

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**submit your answer**A ball strikes a horizontal floor at an angle θ=45°. The coefficient of restitution between the ball and the floor is e=1/2. The fraction of its kinetic energy lost in collision is ?

**Asked By: SIDDHARTH SINGH**5 year ago

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A rigid ring of m
ass 2m and radius 2r is rotating about centre in clockwise direction. Four rigid rings each of mass m and radius r are placed gently on the rim of the ring. Find the moment of inertia of the system.

**Asked By: PANKAJ GUPTA**5 year ago

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