A 5.00-g bullet is fired into a 900-g block of wood suspended as a ballistic pendulum.The combined mass swings up to a height of 8.00 cm.What was the kinetic energy of the bullet immediately before the collision?
A)129 J
B)23.3 kJ
C)0.709 J
D)0.355 J

Question

Quizplus · Accepted Answer

The potential energy at the highest point (mgh) is equal to the initial kinetic energy of the bullet. The combined mass is 905 g (0.905 kg), and the height is 0.08 m. Thus, KE = mgh = 0.905 kg * 9.8 m/s² * 0.08 m = 0.709 J.

A 500-G Bullet Is Fired into a 900-G Block of Wood