A bullet of mass ‘m′, moving with a speed ‘v′ strikes a wooden block of mass M kept at rest and gets embedded in it. The speed of this embedded block will be:
Let the velocity of the embedded block be V.
Given: the mass of bullet is m, and mass of the wooden block is M, initial velocity of the bullet be v.
Using law conservation of momentum:
m1u1+m2u2=m1v1+m2v2
Initially the block is at rest. So u1=0 ms−1
∴ Total momentum before impact = mv
Finally the bullet is embedded in the block
∴Total momentum after impact = (M+m)V
Now, applying conservation of momentum,
mv = (M+m)V
∴V=(mM+m)v