Very short answer questions
I. Choose the correct answer to fill in the blanks.
6. Water vapour
12. Dr. Jakir Hussain
II. Tick (✔) the correct answer.
a) Suppose you are given hot khichdi to eat. How will cool down without blowing air from your mouth?
ii) By spreading it over the plate.
b) Suppose you bang your head while playing and your forehead is swollen, a warmed handkerchief if put over it gives relief. Why is it so?
iii) Warm air soothes the skin giving relief.
c) Some musical instruments are given below. Tick the instrument that we blow air into produce sound.
III. 1 mark questions. (Short answer questions)
1. Because your breath is hotter than your skin.
2. Because air contains Oxygen which helps in the burning and loud blow can extinguish
3. Flute and Been
4. When we blow air on hot potatoes then water molecules escaped into the air because they got enough energy and they change from liquid to a gaseous position.
IV. 2 mark questions. (Long answer questions)
1. The air blown from the mouth is hot and the glass of the spectacles is comparatively colder. The hot air we breathe out contains water vapours which turns into tiny droplets of water when it comes in contact with the colder glass. This makes the glass moist and hazy.
2. During winter, the mirror in the bathroom absorbs the cold air from its environment and makes itself very cold. When a hot shower is taken, the water vapour from the hot water gets in contact with the cold surface of the mirror and condenses to form water droplets.