Important Topics
Sound: two definitions, source, medium, speed, nature.
Exercises
1. Give two illustrations from outside the laboratory of the fact that sound is transmitted by other materials than air.
2. Name the vibrating part that is the source of the sound in three different musical instruments.
3. Is sound transmitted more strongly in solids, liquids or gases? How do you explain this?
4. How far away is a steamboat if the sound of its whistle is heard 10 seconds after the steam is seen, the temperature being 20°C.? Compute in feet and in meters.
5. How many miles away is lightning if the thunder is heard 12 seconds after the flash in seen, the temperature being 25°C.?
6. Four seconds after a flash of lightning is seen the thunder clap is heard. The temperature is 90°F. How far away was the discharge?
7. The report of a gun is heard 3 seconds after the puff of smoke is seen. How far away is the gun if the temperature is 20°C.?