Sound 01

This KS3 Science quiz challenges you on sound. A sound is produced when something vibrates. Sound is used by many species of animal for detecting danger, navigation, predation and communication.

Humans appear to be the only animal that has developed music, which is a specialised form of communication. Sound travels as a wave and so it has a wavelength, speed and frequency. The speed of sound in air is about 330 metres per second. It can only travel through material media.

That means if the soundwave reaches a vacuum, it is stopped. Films that show sound travelling through space are technically incorrect - but they would be really boring without the sound effects! The pitch of a sound depends on its frequency.

Frequency is measured in units called hertz and one hertz means one vibration per second. The higher the frequency, the higher the pitch of the sound. Some sound is so high or low pitched that human ears cannot detect it. These are called ultrasound and infrasound. Stringed instruments are very popular. Thinner strings, tighter strings and shorter strings will vibrate faster than thicker ones, looser ones or longer ones. This enables players of stringed instruments to produce a lot of different musical notes.