Consider two rods of same length and different specific heats (`S_1, S_2`), conductivities (`K_1, K_2`) and area of cross-sections (`A_1, A_2`) and both having temperature `T_1 and T_2` at their ends. If rate of loss of heat due to conduction is equal, then :-

Options

A. `K_1A_1=K_2A_2`
B. `K_2A_1=K_1A_2`
C. `(K_1A_1)/(S_1)=(K_2A_2)/(S_2)`
D. `(K_2A_1)/(S_2)=(K_1A_2)/(S_1)`

Answer

A

Explanation

According to problem, rate of heat loss in both rods is
equal, i.e.,`((dQ)/(dt))_(1)=((dQ)/(dt))_(2)`
`implies(K_1A_1Deltatheta_1)/(l_1)=(K_2A_2Deltatheta_2)/(l_2)`
`K_1A_1=K_2A_2[AsDeltatheta_1=Deltatheta_2=(T_1-T_2)` and `l_1=l_2` given]