Page 70 - Science Class 6 Times Publication

Sound produced by smaller drum is soft whereas the sound produced
by larger drum is loud.

Again, take a smaller drum only. Hit the drum softly. Then, hit the
drum with a stick with more force. What differences do you  nd in

the sound of two cases? In the rst case, sound is soft whereas the
sound is louder in the second case.
Conclusion: i. Larger object produces louder sound.
ii. The object which is hit with more force produces
louder sound.

Propagation of sound

Sound is produced by a vibrating object. Sound passes from one place
to another in the form of wave which is regarded as sound wave.
Sound waves travel through material medium. The material medium
may be solid, liquid or gas. Sound cannot travel in vacuum.

Travelling or movement of sound from one place to another is called
propagation of sound.

Sound can travel through solid
Sound can travel through solid substance. In space, people speak by
using solid medium.

Activity 6.3

To show that sound travels through a solid

Materials required: A scale, desk, etc.
Procedure

1. Tell one of your friends
to keep his/her head
on one end of a desk
with the ear touching
the desk.

2. Hit the another end of
the desk with a scale
softly.

Times' Crucial Science and Environment 66 Book 6