The ballistic pendulum. A bullet of mass m = 30 g is fired into a wooden block

Question:

The ballistic pendulum. A bullet of mass m = 30 g is fired into a wooden block of mass M = 5.0 kg as shown in Figure P7.52. The block is attached to a string of length 1.5 m. The bullet is embedded in the block, causing the block to then swing as shown in the figure. If the block reaches a maximum height h = 0.30 m, what was the initial speed of the bullet?

Figure P7.52