Question

A 7.00-g bullet, when fired from a gun into a 1.00-kg block of wood held in a vise, penetrates the block to a depth of 8.00 cm. This block of wood is next placed on a frictionless horizontal surface, and a second 7.00-g bullet is fired from the gun into the block. To what depth will the bullet penetrate the block in this case?

Answer 1

Answer:

In the second case there's no way to know what depth the bullet will penetrate into the block.

Explanation:

Since the block is on a frictionless surface, when hitted by the bullet, this last one could barely penetrate the surface of the block and, both, start moving as one (perfectly inellastic collition) since here, there's no vise to hold the block into place.