Transmission Of Heat Question 327
Question: The two ends of a conducting rod of varying cross. section are maintained at $ \text{20}{{\text{0}}^{\text{o}}}\text{C} $ and $ {{\text{0}}^{\text{o}}}\text{C} $ respectively in steady state
Options:
A) temperature difference across AB is less than that of across CD
B) temperature difference across AB is greater than of across CD
C) temperature difference across AB is less than that of across CD
D) temperature difference may be equal or different depending on the thermal conductivity
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Answer:
Correct Answer: C
Solution:
[c] Rate of flow of heat $ \frac{dQ}{dt} $ or H will be equal. Temperature difference is given by T.D =(H) (Thermal Resistance) or T.D. $ \alpha $ Thermal Resistance where Thermal resistance $ =\frac{l}{KA} $ Area across CD is less than that across AB. Hence thermal resistance across CD will be more.
Therefore, temperature difference across CD will be more.
BETA
