Question

Explain why

(a) Two bodies at different temperatures T1 and T2 if brought in thermal contact do not necessarily settle to the mean temperature (T1 + T2)/2.

(b) The coolant in a chemical or a nuclear plant (i.e., the liquid used to prevent the different parts of a plant from getting too hot) should have high specific heat.

(c) Air pressure in a car tyre increases during driving.

(d) The climate of a harbour town is more temperate than that of a town in a desert at the same latitude.

Answer 1

(a) when two bodies of different temperatures T1 and T2 are brought in thermal contact then heat flows from the body of higher temperature to lower tempreture unyill temperature become equal . final temperature of the bodies can be the mean temperature .i.e ( T1 + T2)/2 is the final temperature of the bodies .

(b) The coolant in chemical on a nuclear plant is utilized to absorb the heat energy produced in the plant to prevent the different parts of a plant from getting too hot.

Also we know ,
The heat energy absorbed by coolant is directly proportional to specific heat ( Q = mS ∆T , here Q is heat absorbed by coolant and S is specific heat capacity )
So, to absorb more heat energy the specific heat of the coolant should be high.

(c) temperature of tyres as well as air inside it increases during driving due to the friction between tyres and road .
But we know,
According to Charle' s Law ,
Pressure is directly proportional to temperature.
So, air increases in typres during driving .

(d) relative humidity is more than in a desert town . so, the climate of a harbour town is more temperature than that of a town in a desert at the same latitude .

Answer 2

First Question

a) When two bodies at different temperatures T1 and T2 are brought in thermal contact, heat flows from the body at the higher temperature to the body at the lower temperature till equilibrium is achieved, i.e., the temperatures of both the bodies become equal. The equilibrium temperature is equal to the mean temperature (T1 + T2)/2 only when the thermal capacities of both the bodies are equal.