Question
Question: The coefficients of thermal conductivity of copper, mercury and glass are respectively K<sub>c</sub>...
The coefficients of thermal conductivity of copper, mercury and glass are respectively Kc, Km and Kg such that Kc> Km> Kg. If the same quantity of heat is to flow per second per unit area of each and corresponding temperature gradients are respectively Xc, Xm and Xg then
A
Xc= Xm = Xg
B
Xc>Xm>Xg
C
Xc<Xm<Xg
D
Xm<Xc<Xg
Answer
Xc<Xm<Xg
Explanation
Solution
AdQ/dt=K(ΔxΔθ) ⇒ Rate of flow of heat per unit area = Thermal conductivity × Temperature gradient
Temperature gradient (X) ∝Thermal conductivity(K)1
As KC > Km > Kg therefore XC<Xm<Xg.