Two rectangular blocksn A and B of different metals have same length and same area of cross section.They are kept in such away that their cross sectional area touch each other.The temperature at one of A is 100degree celcius and that of B at y the other end is 0 degree celcius.If the ratio of their thermal conductivity is 1:3,then under steady state,the temperature of the junction in contact will be:

The amount of heat flowing per second is :

dQ/dt = KA.dT/L

K₁:K₂ = 1:3

let temp. of junction is T , as heal flow  rate is same

K₁.(100-T) = K_2.(T-0)

temp of junction is 25 C

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