Question

A cylindrical rod has temperatures t1 and t2 at its ends the rate of flow of heat is doubked

Answer 1

H=KA(θ1−θ2)tlRate of heat flow :Q1=Ht=KA(θ1−θ2)lThat is , Q1∝AlDimensions of area=A=[L2]Dimensions of distancel=[L]∴Q∝l⇒Q1Q2=L1L2=2⇒Q1=2Q2