# Need help with an M2 question pleaseWatch

#1
Hi

I would really appreciate help with this question.

It's in the M2 book on page 106, question 7.

A sphere of mass m is moving with a speed V along a horizontal straight line. It collides with an identical sphere of mass m moving along the same straight line in the same direction with speed u (u<V), Sow that the magnitude of the impulse on either of the spheres is (m(1+e)(V-u))/2 where e is the coefficient of restitution between the two spheres.

Thanks for any help.

Michail
0
12 years ago
#2
call the speeds after collision w and x.

impulse = m(v-w)
m(v+u) = m(w+x)
e = (w-x)/(u-v)

eliminate w and x.
0
#3
I'm sorry - I still don't get it...

Isn't e = speed of separation / speed of approach and therefore (x-w)/(v-u) ?

can you get to the end or at least make a couple more steps please?

Michail
0
#4
Anyone? This question is really bugging me...

Michail
0
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