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Titan97
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Homework Statement
Three identical balls (of equal masses) are connected by light inextensible strings and kept on a smooth horizontal surface. The middle ball B is given a velocity ##v_0## at ##t=0##. Find the velocity of ball A when A collides with C.
Homework Equations
Impulse ##J=\Delta P##
The Attempt at a Solution
Since there is no net external horizontal force on the system, acceleration of Centre of Mass along ##x## is zero. Also, ##v_{cm,x}=0##.
Velocity of A and B along the string should be equal to ##v\sin\theta## so that the string does not extend.
Along ##x##, velocity of A is ##v\sin\theta\cos\theta##. If I can assume that all three balls have small radius, the final velocity of A will be equal to velocity of B which varies due to tension.
I tried using work-energy theorem but initially Tension is impulsive and the velocity of A and B increase suddenly. (I am not sure about this but I learned I can't use work-energy theorem when there is a sudden increase in velocity after reading one of the insight articles)
That leaves me with conservation of momentum of the system. Momentum of ball A or C cannot be conserved due to tension. But I am finding it difficult to get the equation.