Concepts

Forces, tension

Overview

Two masses pull a scale in different directions to measure the tension in the string. One mass can be detached and the string held in hand to simulate the string being attached to a wall.

Details

Equipment

• [2] Lab stand
• [2] 90-degree clamp
• [2] Pulley
• [1] 20-N display scale
• [2] Steel brick
• [2] 1-kg mass
• [2] String with hook

Classroom Assembly

1. Place lab stands each with a steel brick on the base.
2. Clamp a pulley to each stand.

Important Notes

• The string may slip out of the pulleys. The string should not be under tension for longer than necessary to do the demo.

Script

1. Hang a mass on the loop side of a string.
2. Lay the string over a pulley and hook it to the scale.
3. Hook the other string to the other side of the scale and lay it over the other pulley.
4. Hang the other mass on the loop side of the other string.

Additional Resources