Solving a Collision Physics Problem: Determining Velocities of Masses A and C

[madahmad1]

Homework Statement

A mass a of 10 kg mass, is attached by a cord to B. When released A swings down and collides with mass c of 20 kg mass which is vertically below B. if the coefficient of restitution is 0.5 and A and C are assumed to be point masses, determine the velocity of A and C immediately after impact.

Answer is - A 0 m/s, C- 3.13m/s but i do not know hot to get it.

Homework Equations

The Attempt at a Solution

I know that we evaluate the situation before impact and after impact.
Can someone help? Also I need to know if it is elastic or not.

 

[tiny-tim]

… Also I need to know if it is elastic or not.

No, it's not elastic … see

http://en.wikipedia.org/wiki/Coefficient_of_restitution​

 

[madahmad1]

so that means that we have to find the difference in the initial velocity and final velocity for both objects right?