Transmission Of Heat Question 26
Question: Which of the following cylindrical rods will conduct most heat, when their ends are maintained at the same steady temperature
[CPMT 1981; NCERT 1973, 81; MP PMT 1987; CBSE PMT 1995]
Options:
A) Length 1 m; radius 1 cm
B) Length 2 m; radius 1 cm
C) Length 2 m; radius 2 cm
D) Length 1 m; radius 2 cm
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Answer:
Correct Answer: D
Solution:
$ \theta =\frac{K _{1}{\theta _{1}}+K _{2}{\theta _{2}}}{K _{1}+K _{2}} $
Therefore $ \frac{K _{1}}{K _{2}}=\frac{5}{3} $
$ K _{1}=5K $
$ K _{2}=3K $ is maximum in option (d), hence it will conduct more heat.
BETA
