10.Sound-Production of sound

• We hear many sounds all day.• Eg.people-talk• rattling –vehicles• clanging –pots and pans• ringing-bells• rustling-leaves• melodious music-radio

Vibration

• Vibration is necessary for sound to be produced.

• What is a vibration?• When an object moves very

fast following a fixed path from one side to the other and then back again,we say that it vibrates.

Period of oscillation- The time taken by a pendulum to

complete one swing or oscillation is called period of oscillation.

Frequency- The number of oscillations that an

object completes in one second is called Frequency

Amplitude – The maximum distance that the

pendulum moves away from its position at rest is called the amplitude of oscillation.

AUDIBLE -INAUDIBLE SOUNDS

• The human hear a sound of frequency between 20Hz to20000Hz.These sounds are called audible sounds.

• The human can not hear the sounds of frequency less than 20Hz and more than 20000Hz. These sounds are called inaudible sounds.

• Dogs,bats can hear ultrasonic sounds