What is the temperature of the steel-copper junction in the steady-state of the system shown in the figure?
The 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 the cross section of the steel rod is twice that of the copper rod.
(Thermal conductivity of steel = ; and of copper = ).
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4.
An iron bar \(\left(L_{1} = 0 . 1 m , A_{1} = 0 . 02 m^{2} , K_{1} = 79 W m^{- 1} K^{- 1}\right)\) and a brass bar \(\left(L_{2} = 0 . 1 m , A_{2} = 0 . 02 m^{2} , K_{2} = 109 W m^{- 1} K^{- 1}\right)\) are soldered end to end as shown in the figure. The free ends of the iron bar and brass bar are maintained at 373 K and 273 K respectively. The temperature of the junction of the two bars is:
1. 215 K
2. 315 K
3. 415 K
4.115 K
An iron bar and a brass bar are soldered end to end as shown in the figure. The free ends of the iron bar and brass bar are maintained at 373 K and 273 K respectively and the The equivalent thermal conductivity of the compound bar is:
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2.
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4.
An iron bar \(\left(L_{1} = 0 . 1 m , A_{1} 0 . 02 m^{2} , K_{1} = 79 W m^{- 1} K^{- 1}\right)\) and a brass bar \(\left(L_{2} = 0 . 1 m , A_{2} = 0 . 02 m^{2} , K_{2} = 109 W m^{- 1} K^{- 1}\right)\) are soldered end to end as shown in the figure. The free ends of the iron bar and brass bar are maintained at 373 K and 273 K respectively. The heat current through the compound bar is:
1. 916.1 W
2. 826.1 W
3. 926.1 W
4. 726 W