Question

5. In a tropical country, during summers, which of the following materials is likely to
absorb the least heat? (applying)
(a) Yellow, rayon cloth (b) White cotton cloth
(c) Blue denim cloth
(d) Maroon silk cloth

6. What role does the kink play in making the process of reading temperatures easier, and
in which kind of thermometer does it help? (Understanding) )
(a) Kink inside the clinical thermometer prevents the mercury thread from falling.
(b) Kink inside the laboratory thermometer lowers the mercury thread, faster.
(c) Kink inside the laboratory thermometer requires it to be held still.
(d) Kink inside the clinical thermometer requires it to be held upright.

7. Which of these is the best example of heat transfer by radiation? (applying)
a) butter melting on warm bread
b) warming of the outer surface of a satellite by sunlight
c) a rod of iron heated by a blacksmith before hammering it
d) air of a room cooled by an air-conditioner fixed at the top of the room​

Answer 1

Answer:

5.b) white cotton cloth

6. a) Kink inside the clinical thermometer prevents the mercury thread from falling.

7. d) air of a room cooled by an air-conditioner fixed at the top of the room​

         

Answer 2

The answers to the above questions are as follows :

5) In a tropical country, during summers white cotton cloth is likely to absorb less heat.

- White clothes are preferred in summer as white clothes reflect most of the sun's heat and absorb the very less amount of the sun's heat by keeping our body cool.

- Similarly, in winter we prefer black clothes as they absorb more heat and keep our body warm.

6) The correct option is

a) Kink inside the clinical thermometer prevents the mercury from falling.

- The Kink is used to prevent the backflow of mercury into the thermometer bulb when the thermometer bulb is removed from the patient's mouth.

- Kink is a constriction in a glass tube just above the mercury bulb.

7) The best example of heat transfer by radiation is d) air of room cooled by air - conditioner fixed at the top of the room.

- Heat transfer by radiation occurs in infrared radiation, microwaves, visible light is emitted or absorbed.

- Examples are heating from stove burner, visible light from a candle.