Transmission Of Heat Question 51

Question: Two identical plates of different metals are joined to form a single plate whose thickness is double the thickness of each plate. If the coefficients of conductivity of each plate are 2 and 3 respectively, then the conductivity of composite plate will be

Options:

A) 5

B) 2.4

C) 1.5

D) 1.2

Show Answer

Answer:

Correct Answer: B

Solution:

Thermal conductivity of composite plate $ K _{eq}=\frac{2K _{1}K _{2}}{K _{1}+K _{2}}=\frac{2\times 2\times 3}{2+3} $

$ =\frac{12}{5} $ =2.4