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Que. A hollow sphere (k = 30 W/m K) of inner radius 6 cm and outside radius 8 cm has a heat generation rate of 4000000 W/m³. The inside surface is insulated and heat is removed by convection over the outside surface by a fluid at 100 degree Celsius with surface conductance 300 W/m² K. Make calculations for the temperature at the outside surfaces of the sphere
a. 105.6 degree Celsius
b. 205.6 degree Celsius
c. 305.6 degree Celsius
d. 405.6 degree Celsius
Correct Answer:305.6 degree Celsius
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