Exams › JEE Advanced › Physics
Four rods made of the same material but with different radii r and lengths l connect two heat reservoirs held at different temperatures. Which rod conducts the most heat?
- r = 2 cm, l = 0.5 m
- r = 2 cm, l = 2 m
- r = 0.5 cm, l = 0.5 m
- r = 1 cm, l = 1 m
Correct answer: r = 2 cm, l = 0.5 m
Solution
Heat current is proportional to r²/l; this is maximised by the largest radius and smallest length, r = 2 cm, l = 0.5 m.
Related JEE Advanced Physics questions
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