Oscillating String
Light, Sound and Waves
TV Strobe Light
Enrichment Activity for 5-11 11-14
- Level Elementary
What you need
- A cathode ray tube television (turned on!)
- A rubber band
Instructions
- Stretch the rubber band between your thumb and first finger
- Holding the band between you and the television screen, pluck one side
Results and Explanation
You should see the band make zig zag shapes. The television picture is made up of tiny dots flashing on and off. It acts like a strobe light, freezing the band's vibrations at different positions so it looks like it's moving in slow motion.
These experiments have not been specifically safety tested for home use but we believe them to be safe if the instructions are followed. Adult supervision or direction is recommended as appropriate. All experiments are carried out at your own risk.
