What is the temperature of the steel-copper junction in the steady state of the system shown in Fig. 11.15. Length of the steel rod = 15.0 cm, length of the copper rod = 10.0 cm, temperature of the furnace `= 300^(@)C`, temperature of the other end = `0^(@)C`. The area of cross section of the steel rod is twice that of the copper rod. (Thermal conductivity of steel `= 50.2 J s^(–1) m^(–1)K^(–1)`, and of copper `= 385 J s^(–1)m^(–1)K^(–1))`.

Explanation

`(k_1A_1(T_1-T))/(L_1)=(k_2A_2(T-T_2))/(L_2)`
`300-T=((L_1)/(L_2))((k_2)/(k_1))((A_2)/(A_1))(T-0)`
`300-T=2T`
`T=100^@C`