Question

Q1) Write true or false for each statement

(a) On touching a lump of ice, we feel cold because some heat passes from our body to the ice.

(b) Heat flows from a body at high temperature to a body at a low temperature when they are kept in contact

(c) All solids expand by the same amount when heated to the same rise in temperature (a) Telephone wires are kept tight between the two poles in summer.

(e) Transfer of heat by radiation requires a medium

(g) A Solids are best conductor of heat

(g) A mercury thermoracter makes use of the property of expansion of liquids on heating.

(h) Molecules gain energy on heating o Watzr is a bad conductor of heat.

(i) Medium is necessary for the transfer of heat by radiation

(j) Land and sea breezes are convection currents of cold and warm air.




ch-4 heat NCERT
class 7​

Answer 1

Answer:

Solution:

(a) true

(b) true

(c) false

(d) false

(e) true

(f) true

(g) true

(h) false

(i) true

(j) false

Answer 2

Answer:true false

1 true

2 true

3 false

4 false

5false

6 true

7 true

Explanation: