Guys I'm having a little problem in undersatnding a few things:(adsbygoogle = window.adsbygoogle || []).push({});

We have a wall and a ball of mass 'm'. The ball is thrown towards the wall with speed u and rebounds with speed 'v'. The coefficient of restitution is, e is 1/3. The question is to find the value of 'v'.

Thats how I think it should be solved:

mu=mv (since the final velocity of the wall is "CONSIDERED" zero)

=> u=v

Now if I apply newton's law of restitution and simplify:

v=-eu (putting this into u=v gives us)

u=-eu

cancelling u gives e=-1 but e=1/3. Where did I go wrong? I just cant understand it.

Any help will be greatly appreciated.

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