Question 1

Sound is produced by which of the following?

Accepted Answer

Sound is produced by vibrating objects. When an object vibrates, it sets the surrounding particles of the medium into motion, creating a sound wave that travels through the medium to our ears.

Question 2

In humans, sound is produced by the:

Accepted Answer

In humans, sound is produced by the voice box or the larynx. When the lungs force air through the two vocal cords, they vibrate to produce sound.

Question 3

Sound needs a to travel.

Accepted Answer

Sound needs a material medium (solid, liquid, or gas) to travel. It cannot travel through a vacuum because there are no particles to transmit the vibrations.

Question 4

Which of the following mediums cannot transmit sound?

Accepted Answer

Vacuum cannot transmit sound. Since sound is a mechanical wave, it requires a medium containing particles to propagate, which is absent in a vacuum.

Question 5

The part of the ear that acts like a stretched rubber sheet and vibrates when sound falls on it is:

Accepted Answer

The eardrum acts like a stretched rubber sheet. When sound vibrations hit the eardrum, it vibrates and sends signals to the inner ear.

Sound — NCERT Class 8 Science Important Questions & Revision Notes