A cylindrical rod having temperature `T_(1)` and `T_(2)` at its ends. The rate of flow of heat is `Q_(1) cal//sec`. If all the linear dimensions are doubled keeping temperature constant, then rate of flow of heat `Q_(2)` will beA. `4 Q_(1)`B. `2 Q_(1)`C. `Q_(1)/4`D. `Q_(1)/2`

A cylindrical rod having temperature `T_(1)` and `T_(2)` at its ends.

1.	A cylindrical rod having temperature `T_(1)` and `T_(2)` at its ends. The rate of flow of heat is `Q_(1) cal//sec`. If all the linear dimensions are doubled keeping temperature constant, then rate of flow of heat `Q_(2)` will beA. `4 Q_(1)`B. `2 Q_(1)`C. `Q_(1)/4`D. `Q_(1)/2`
Answer» Correct Answer - B Rate of heat flow `(Q/t) = (kpir^(2)(theta_(1)-theta_(2)))/(L) prop (r^2)/(L)` `:. (Q_1)/(Q_2) = ((r_1)/(r_2))^(2)((l_2)/(l_1)) = (1/2)^(2)xx(2/1) = 1/2` `rArr Q_(2) = 2Q_(1)`.

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A cylindrical rod having temperature `T_(1)` and `T_(2)` at its ends. The rate of flow of heat is `Q_(1) cal//sec`. If all the linear dimensions are doubled keeping temperature constant, then rate of flow of heat `Q_(2)` will beA. `4 Q_(1)`B. `2 Q_(1)`C. `Q_(1)/4`D. `Q_(1)/2`

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