C - Waves - Sound - Analogue & Digital Signals

Question 1

What is the range of human hearing?

Answer 1

20 hz - 20,000 hz

Question 2

What type of waves are sound waves?

Answer 2

longitudinal

Question 3

Sound waves can be ________ and __________.

Answer 3

Sound waves can be reflected and refracted.

Question 4

Describe how you could measure the speed of sound in air

Answer 4

Use the tape to measure a distance of 50 metres from the wall.Now clap your hands and check you can clearly hear an echo from the wall. Make sure the echo isn’t coming from other walls in the area. The time it takes sound to run 100 metres is the time difference between when you clap and when you hear the echo.However, measuring that single short burst of time is difficult.Now clap repeatedly in time with the echo, so that you can only hear your own clap (the echo is masked by your next clap)Now measure the time it takes to clap 10 times. Get a friend to start the stopwatch at the first clap and end it when you hear the echo of the 10th clap.We now know how long it takes for sound to travel 1 kilometre.Now we can calculate the speed of sound using: speed = distance/time