This is a simulation of a ballistic pendulum. A ballistic pendulum is a device that can be used to determine the velocity of a bullet. A bullet of known mass is shot into a wood block of known mass. After the collision, the bullet is embedded in the wood block and the wood block swings upward. Use the vertical slider to find the maximum height reached by the bottom of the wood block. Use the arrow keys on your keyboard to make fine adjustments. Using the known masses of the bullet and the block as well as the vertical height reached, you can use energy and momentum conservation concepts to determine the initial velocity of the bullet just before it hit the wood block. Enter your answer in the input box at the bottom of the simulation and hit enter to see whether it is correct (within one percent). Keep trying until you enter the correct value.