The Fall/Drop Shooter Demo

Theory

In any sort of collision, there is a transfer of energy from one object to the other. This specific collision is called an elastic collision. It may seem different to a student because of the use of an intermediate object: the 18 inch bar. But the principle is still the same. Both energy and momentum are conserved during the collision.

The reason why no energy is lost in the bar when the hammer strikes it is be cause it is secured to a sturdy, massive structure with a clamp. A tighter clamp will give the better interface between the hammer and the ball.

The bar is used so that we can also prove newton's law which states that masses fall at the same rate

Apparatus

The equipment needed for this demo is:

* Two steel balls
* A hammer
* The 18 inch steel strip
* A clamp
* A balance

Procedure

Clamp the 18 inch aluminum bar to a sturdy table with the end hanging over the edge. One steel marble should be placed on either side of the bar. Measure the mass of the two marbles with one of the balances in the lab.

Striking the bar with a hammer will cause the ball which is resting on the same side as the hammer to drop straight down but the ball on the other side will receive the kinetic energy from the hammer and will be propelled forward as it drops.

The position of the second ball when it drops can be used to solve for the force with which the hammer struck the bar because using what we know of vectors and the acceleration due to gravity, we can find the initial velocity of the ball.