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Three rods of the same dimensions have t...

Three rods of the same dimensions have thermal conductivities `3`k , `2`k and k . They are arranged as shown, with their ends at `100^(@)C, 50^(@)C` and `0^(@)C`. The temperature of their junction is :-

A

`75^(@)C`

B

`(200)/(3)"^(@)C`

C

`40^(@)C`

D

`(100)/(3)"^(@)C`

Text Solution

Verified by Experts

The correct Answer is:
B
Let `theta` = junction temperature Net heat current at junction is zero
`3k(100-theta) + k(0-theta) +2k(50-theta) = 0 implies theta= (200)/(3) "^(@)C`
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