A 1.5 kilogram block is at rest on a horizontal frictionless surface. The block is attached to a spring that is itself fixed to the wall. The block is resting at the equilibrium point of the spring. The spring constant is 1500 N/m. A 25 gram bullet is fired into the opposite end of the block that causes the spring to be compressed 15 centimeter.
a. Find the speed of the bullet and block just after impact?
b. Find what was the initial speed of the bullet?