Telecommunication Sound Waves Sound energy travels in the

Telecommunication. Sound Waves. • Sound energy travels in the form of waves. • Sound can travel through solids , liquids and gases by vibrating the particles in the three types of materials.

Telecommunication. Sound Waves. • The particles in the three materials vibrate in the same direction as the wave motion. • This wave is called a Longitudinal Wave Sound waves cannot travel in a vacuum.

Telecommunications. Sound Waves. • These waves then vibrate our ear drums which then activate small bones in our inner ear. • A diagram of the ear is shown.

Telecommunication. The Ear. bones Ear drum Outer ear

Telecommunication. The difference between sound and light waves. • Sound waves travel very much slower than light waves. • This can be seen by observing a thunder and lightning storm. • The light reaches us quickly but the sound from the thunder comes later.

Telecommunication The speed of sound. • The speed of sound can be measured by by using two microphones and an electronic timer. • When the sound reaches the first mic, the timer starts. When the sound reaches the second mic, the timer stops. • If we know the distance between the two mics (say one metre) and the time , we can work out the speed. This is shown on the next slide.

TELECOMMUNICATION. THE SPEED OF SOUND. Time = 0. 003 s Mic 2 Mic 1 Sound here Distance = 1 metre

Telecommunication. Calculation of The Speed of Sound • The Speed of Sound can be calculated as shown below. • Speed = distance time = 1/0. 003 = 330 m / s

Telecommunication. The difference between sound and light waves. • Light is a transverse wave. The particles move at right angles to the wave as shown.