A rifle of mass M is intially at rest but free to recoil. It fires a bullet of mass m and velocity v (relative to the ground). After firing, the velocity of the rifle (relative to the ground) is:(adsbygoogle = window.adsbygoogle || []).push({});

P= m2V2 -m1v1

P= M(v-0) - m(v-0)

M(V-0) = m(V-0)

V-0= mv/M

V= -mv/M

is that right

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# Homework Help: Equation for momentum

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