The pipe organ
Strike the pipes and note the pitch of the sounds. Try to play a simple melody.
How it works
The length of the pipe determines the length of the sound wave it produces, hence the pitch of the sound. The length of the sound wave is four times the length of the pipe. The longest pipe is 280 cm long, producing sound at a frequency of 30 Hz; the shortest pipe is 90 cm long and it produces sound at a frequency of about 95 Hz.
The human can hear sounds between the frequencies of 20 Hz – 20 000 Hz. As we get older, this range diminishes. Dogs can hear sounds up to 40 000 Hz, bats – 100 000 Hz and dolphins – 200 000 Hz.