Page 143 - Science Class 08

Project ActivityActivityActivity
Project
Project
Project Activity
A. Make a chart to show how sound is produced and how it travels. Hang it in your classroom.
B. Can you write the approximate sound level of the followings.

Sound Sound level in dB

Whispering 25

Conversa on 65

Light vehicles 70

Heavy vehicles 105

Loud music 110

Jet aeroplane 130 and above

C. Make a Jal Tarang, take 8 glasses of the same size. Fill them with water to different levels.
Strike them one-by-one with a pencil. Do they emit sound of different frequencies? Take the
help of your music teacher to adjust the level of water in the glasses so that you can get the
notes sa, re, ga, ma, pa, dha, ni, sa. Your Jal Tarang is ready to play.

HO
HOTSTSTS
HO
HOTS
In the game hide-and-seek, how can the blind-folded person guess which player is close to him and
the other is far from him?

Science-8 143