Physics, asked by janibjavid3, 6 hours ago

9 class since chapter sounds A&Q

Answers

Answered by ItsPapakaPara
1

Given:-

1. What is sound and how is it produced?

Solution:

Sound is produced due to vibrations. When a body vibrates, it forces the adjacent particles of the medium to vibrate. This results in a disturbance in the medium, which travels as waves and reaches the ear. Hence, sound is produced.

2. Describe with the help of a diagram, how compressions and rarefactions are produced in the air near a source of sound.

Solution:

When the school bell is hit with a hammer, it moves forward and backwards producing compression and rarefaction due to vibrations. When it moves forward, it creates high pressure in its surrounding area. This high-pressure region is known as compression. When it moves backwards, it creates a low-pressure region in its surrounding. This region is called rarefaction.

3. Cite an experiment to show that sound needs a material medium for its propagation.

Solution:

Take an electric bell and hang it inside an empty bell-jar which is fitted with a vacuum pump (as shown in the figure below).

Initially, one can hear the sound of the ringing bell. Now, pump out some air from the bell-jar using the vacuum pump. You will realize that the sound of the ringing bell decreases. If you keep on pumping the air out of the bell-jar, then glass-jar will be devoid of any air after some time. Now try to ring the bell. No sound is heard but you can see bell prong is still vibrating. When there is no air present in the bell jar, a vacuum is produced. Sound cannot travel through vacuum. Therefore, this experiment shows that sound needs a material medium for its propagation.

4. Why is sound wave called a longitudinal wave?

Solution:

The vibration of the medium that travels parallel to the direction of the wave or along in the direction of the wave, is called a longitudinal wave. The direction of particles of the medium vibrates parallel to the direction of the propagation of disturbance. Therefore, a sound wave is called a longitudinal wave.

Answered by shristisingh2618
1

Answer:

1. How does the sound produced by a vibrating object in a medium reach your ear?

Solution:

When an object vibrates, it necessitates the surrounding particles of the medium to vibrate. The particles that are adjacent to vibrating particles are forced to vibrate. Hence, the sound produced by a vibrating object in a medium is transferred from particle to particle till it reaches your ear.

Section 12.2 Page: 163

1. Explain how sound is produced by your school bell.

Solution:

When the school bell is hit with a hammer, it moves forward and backwards producing compression and rarefaction due to vibrations. This is how sound is produced by the school bell.

2. Why are sound waves called mechanical waves?

Solution:

Sound waves require a medium to propagate to interact with the particles present in it. Therefore, sound waves are called mechanical waves.

3. Suppose you and your friend are on the moon. Will you be able to hear any sound produced by your friend?

Solution:

No. Sound waves require a medium to propagate. Due to the absence of atmosphere on the moon and since sound cannot travel in vacuum, I will not be able to hear any sound produced by my friend.

Similar questions