Question

A bullet of mass 3.9 g was fired at a stationary ball of lead. The head on impact moved the 10 kg ball at a velocity of .3703 m/s. If energy losses due to heat and internal energy are ignored. What was the speed of the bullet?
Steve
If the bullet penetrated the lead and stayed there, then to conserve momentum,

.0039v = (10.0039)(.3703)