Question

What do you mean by a vibratory motion ?
What is sound ? 91
How is sound produced ?
Describe an experiment to show that each source
of sound is a vibrating body.
Name two sources of sound.
How do we produce sound ?​

Answer 1

A type of motion in which a particle moves to and fro about a fixed point is known as vibratory motion. For e.g., pendulums, swings, tuning fork

Answer 2

What do you mean by a vibratory motion ?

Ans - The To and Fro motion of a body is called vibration.

• Here, The motion in which body is vibrating called vibratory motion.

What is sound ?

Ans - Sound is a form of mechanical energy that produces sensation of hearing.

• Sound is an unavoidable and integral part of our lives.

How is sound produced ?

Ans - Let us discuss some activities to answer this question.

Activity - 1

• Fix a rubber band tightly on an empty matchbox.

• Pluck the rubber band and keep it close to your ear.

• We can hear the sound when the rubber band vibrates.

Activity - 2

• Blow air into papers of your notebook.

• What do you notice?

• We notice that, the papers of note book vibrates fast and produce sound.

In all these activities, we have noticed that objects vibrate and produce sound. In this way, Sound is produced.

Describe an experiment to show that each source of sound is a vibrating body ?

Ans - Fill a plate with water and let the water settle.

Strike the rim of the plate with a spoon.

Conclusion :-

We observe that, the water gets disturbed, the plate vibrates and we can hear the sound.

Thus, Each source of sound is a vibrating body.

Name two sources of sound ?

Ans - Natural and man-made.

Natural - People , birds animals etc

Man-made - autos, motorbikes, buses, lorries, tractors, trains

and music from loudspeakers at public places, television, etc.

How do we produce sound ?

Sound can be produced by - People talking, birds chirping, cries of animals, sounds of autos, motorbikes, buses, lorries, tractors, trains and music from loudspeakers at public places, television, etc$.$