The heat is flowing through two cylinderical rods of same material. The diameters of the rods are in the ratio `1:2` and their lengths are in the ratio `2:1`. If the temperature difference between their ends is the same, the ratio of rates of flow of heat through them will beA. `1 : 4`B. `4 : 1`C. `1 : 8`D. `8 : 1`

The heat is flowing through two cylinderical rods of same material. Th

1.	The heat is flowing through two cylinderical rods of same material. The diameters of the rods are in the ratio `1:2` and their lengths are in the ratio `2:1`. If the temperature difference between their ends is the same, the ratio of rates of flow of heat through them will beA. `1 : 4`B. `4 : 1`C. `1 : 8`D. `8 : 1`
Answer» Correct Answer - C (3) `(r_(1))/(r_(2)) = (1)/(2), (l_(1))/(l_(2)) = (2)/(1)` `(i_(1))/(i_(2)) = (R_(2))/(R_(1)) = (l_(2))/(l_(1)). (r_(1)^(2))/(r_(2)^(2)) = (1)/(2) ((1)/(2))^(2) = (1)/(8)`

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