Maximum potential energy after collision

AI Thread Summary
The discussion revolves around calculating the maximum potential energy stored in a system during an elastic collision between two balls, where one ball is stationary and has a mass n times that of the moving ball. The participant confirms their calculations using the principles of conservation of mechanical energy and linear momentum, arriving at the expression U = En/(n+1) for potential energy. They seek validation of their concept and calculations, which are affirmed by other contributors. An alternative approach using the center of momentum reference frame is suggested for further exploration. The thread concludes with a positive acknowledgment of the participant's understanding and calculations.
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Homework Statement

: A ball a, moving with kinetic energy E, makes a head on elastic collision with a stationary ball with mass n times that of A. The maximum potential energy stored in the system during the collision is
a)nE/(n+1)
b)(n+1)E/n
c)(n-1)E/n
d)E/n[/B]

Homework Equations

:Principle of Conservation of mechanical energy(PCME) and principle of conservation of linear momentum(PCLM)[/B]

The Attempt at a Solution

: I have done the sum and my answer matches correctly...I just want to confirm if my concept is correct.
Just at the instant when potential energy of the system is maximum, the two balls are moving with equal velocities(just at that instant).
So from PCLM[/B]
mu=m(n+1)V
where u=initial velocity
V=the common velocity

Now since the collision is elastic, we can conserve ME.
so

1/2mu2=1/2m(n+1)V2+ U
where U= P.E
Also
E=1/2mu2
so from the two equations above...I got
U = En/(n+1)
I just want to assure if my concept is correct
Sorry if the thread is a duplicate one...or if I've made any grammatical error...
Thanks for the help
 
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Looks good to me.

You could also consider using the centre of momentum reference frame, which might offer a neat alternative approach.
 
PeroK said:
Looks good to me.

You could also consider using the centre of momentum reference frame, which might offer a neat alternative approach.
Thanks for your help
 
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