Science [1 Marks Each] QUE - ANS

It is advised to cover a burning man with blanket so that the air supply is cut off and the fire can be extinguished.

Wind helps spreading seeds of many plants and pollen grains.

When air hits the sail of a boat it pushes the boat forward and the boat moves.

When chilled water is filled in a glass tumbler, the outer surface becomes dim and water droplets appear on the outer surface of the glass.

If a burning candle is covered with glass the candle gets extinguished.

When an empty bottle held upside down in a bucket filled with water is tilted, air bubbles start coming out of the bottle and water starts entering into it.

Water vapour present in air in the form of moisture, snow, hail and water droplets.

Carbon dioxide gas is given out in the process of respiration.

Solid particles like dust, pollen grains and smoke are present in air.

Photosynthesis

Nitrogen and oxygen

Water vapour

Nitrogen

Oxygen

Small pores are present between the fibres of cotton wool. Sufficient volume of air is present in these pores. When a lump of cotton wool is dipped in water, this air is replaced by less volume of water, so the cotton wool shrinks.

Oxygen gas in the atmosphere is essential for respiration.