The coefficient of the thermal conductivity of copper is 9 times that of steel . In the composite sylindrical bar shown in the figure , what will be the temperature at the junction of copper and steel ?

The coefficient of the thermal conductivity of copper is 9 times that

1.	The coefficient of the thermal conductivity of copper is 9 times that of steel . In the composite sylindrical bar shown in the figure , what will be the temperature at the junction of copper and steel ?
Answer» `75^(@)` `33^(@)` `65^(@)` `25^(@)` SOLUTION :Let T be the temp. of junction. `:.` In EQUILIBRIUM `Q_(1)=Q_(2)`. `:.(k_(1)A(100-T)t)/(18)=(k_(2)A(T-0)t)/(6)` `rArr(9k_(2)(100-T))/(18)(k_(2)T)/(6)rArrT=75^(@)C` Correct choice is (a).

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The coefficient of the thermal conductivity of copper is 9 times that of steel . In the composite sylindrical bar shown in the figure , what will be the temperature at the junction of copper and steel ?

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