Collisions In Two Dimensions

The purpose of this lab is studying about the momentum and energy of two ball during collision.
In the first section, we need to watch the steel ball impacting another steel ball and determine the energy and momentum. Therefore, we set up a flat plate and collect the motion of two balls with camera.

data:

mass of steel ball: 115.5 g

mass of aluminum ball : 72 g

All of first, we make the steel ball to impact another ball.

To determine the position and velocity of two balls, we use program to points two balls in each half second. And then, we can calculate their velocity with computer.

From this table, we can make a graph to describing the shape how their motion is in x,y dimensions.

From this graph, we get the velocity of two balls in two dimensions,

and we can calculate their momentum:

After studying, we are able to see that the total kinetic energy decreases, and the momentum changes a little.

For the second part, we use the aluminum to impact the steel ball.

And then we do the same thing to determine the velocity of two balls.

Thus, we get the table:

From this table, we can make the graph:

and then, we calculate the momentum of the two balls,and we found the two momentum is big but it is all right, so there may be some thing wrong. But the kinetic energy still decreases.

conclusion, the momentum of the system does not change much when collision, but the kinetic energy will decreases.