Question
Physics Question on Heat Transfer
Given below are two statements: One is labelled as Assertion A and the other is labelled as Reason R.
Assertion A: Houses made of concrete roofs overlaid with foam keep the room hotter during summer.
Reason R: The layer of foam insulation prohibits heat transfer, as it contains air pockets.
In the light of the above statements, choose the correct answer from the options given below.
A is true but R is false.
A is false but R is true.
Both A and R are true and R is the correct explanation of A.
Both A and R true but R is NOT the correct explanation of A.
A is false but R is true.
Solution
Reason R is true : Foam insulation reduces heat transfer due to the presence of air pockets which are poor conductors of heat. However, Assertion A is false. Foam insulation is used to keep the room cooler during summer and warmer during winter by acting as a heat insulator.