Question

A rod AB is 1m long. The temperature of its one end A is maintained at `100^(@)`C and other end B at `10^(@)`C, the temperature at a distance of 60 cm from point B is
A. `64^(@)`C
B. `36^(@)`C
C. `46^(@)`C
D. `72^(@)`C

Answer 1

Correct Answer - A
let the temperature at distance 60 cm from point B to `theta`

Where, K = coefficient of thermal conductivity, A=area of rod
`(KA(100-theta))/(40) = (KA(theta-10))/60`
or `(100-theta)/2 = (theta-10)/3`
or `300 -3theta = 2theta-20` or `5theta = 320` or `theta=64^(@)`C