Page 76 - Science class 4

4. In filtration, water is passed through ___________ paper.

(a) carbon (b) coloured

(c) filter (d) none of these

High Order Thinking Skill (HOTS)

1. The weather in costal areas is not as cold as in other regions in winters.

Why?
2. After a cold night, why we see dew drops on the ground and other surfaces?

Learn ‘N’ Fun

Complete the following diagram :

METHODS OF PURIFICATION OF WATERETHODS OF PURIFICATION OF WATERETHODS OF PURIFICATION OF WATER
M M

Boilingoilingoiling F F
B B
Filtrationiltrationiltration

Testing Zone

Take samples of water from various sources.

Keep them in different transparent glasses.

Observe them minutely and find out which source of water is the purest one, fit

for drinking.

Can we make out by looking at the sample that this is not worth drinking?

Practical Approach

Land heats faster than water.
Take two bowls. Put water in one

and sand in the other. Measure
their temperatures. Then put the

bowls in the sun for an hour.

Note the temperature again. You
Sand
Sand
Water
Water
Water
Water
Sand Water Sand Water
Sand
Sand
will notice that sand gets heated
up faster than water.