Question

One end of a metal rod of length L and cross-sectional area A is held at a constant temperature T₁. The other end is held at a constant T₂. Which of the statements about the amount of heat transferred through the rod per unit time are true?

I.The rate of heat transfer is proportional to 1/(T₁ - T₂).

II. The rate of heat transfer is proportional to A

III. The rate of heat transfer is proportional to L.

(A) II only

(B) III only

(C) I and II only 

(D) I and III only 

(E) II and III only

Answer 1

Correct option (A) II only

Explanation:

H = KA∆T/L