丁香园AV

Concepts

Relative motion

Overview

A toy tractor moves across a piece of paper being pulled along the floor.

Details

Equipment

• [1] Tractor toy
• [1] Large piece of paper
• [2] Metre stick
• [2] Lab stand
• [2] 90-degree clamp
• [1] Aluminum rod
• [1] Document camera
• [1] Lab jack

Classroom Assembly

1. Place the paper flat on the floor.
2. Slip metre sticks into pockets on the sides of the paper.
3. Clamp the rod to the lab stands to make a diagonal over the paper.
4. Mount the camera on the lab jack to have an overhead view of the demo.
5. Plug the camera into power and the video input for the projector.
6. Check that the camera works.

Important Notes

• The tractor's battery compartment needs to be securely taped shut for it to work.

Script

1. Turn on the tractor.
2. Using the metre sticks as handles, move the paper so that the tractor travels along the rod.
3. Turn off the tractor.

Additional Resources