1. The problem statement, all variables and given/known data A 7.00 g bullet, when fired from a gun into a 1.10 kg block of wood held in a vise, penetrates the block to a depth of 6.40 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? 2. Relevant equations vf^2 = vi^2 + 2ad p = mv m1v1i + m2v2i = (m1+m2)vf Δp = ƩF dt 3. The attempt at a solution Honestly, I'm pretty baffled. I can't do anything with momentum without an initial velocity, and I can't find that without acceleration or time. I've seen some other posts that talk about resistive force, but we haven't discussed that so I don't think that's necessary. I think the vise is what's throwing me for a loop. It's inelastic, so there no conserved energy. I'm just not sure what the first step is.