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Clickety-Clack: The Transfer of Force

What You Need:

• Two boards about the same size
• Tape
• About 6 marbles of equal size

Tip: You can use two yardsticks in place of the boards.

Question: What happens when objects collide?

1) First, tape the boards to the floor about 1/2 inch apart, so that the marbles roll in the track .

2) Then, put one marble at one end of the track and roll the other marble at it. What do you notice happens when the marbles collide?

3) Now, put two marbles together so they touch. Roll one marble into them. What happens when the marbles collide?

4) Can you explain what happens to the marbles in these collisions?

A Scientific Explanation:

The moving marble has momentum. Momentum is the energy a moving object carries with it as it moves. When the object collides, the momentum transfers, or moves, to the other object. When one object collides into two objects only one of the two objects moves forward. This is because the amount of momentum you begin with always remains the same.


Roll two marbles into three marbles. Then experiment with different combinations of marbles and distances between marbles. Can you explain what happens in each collision?