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A composite block is made of slabs A,B,C...

A composite block is made of slabs A,B,C,D and E of different thermal conductivities (given in terms of a constant K) and sizes (given in terms of length, L) as shown in the figure. All slabs are of same width. Heat 'Q' flows only from left to right through the blocks.
Then in steady state

A

heat flow through A and E slabs are same.

B

heat flow through slab E is maximum

C

temperature difference across slab E is smallest.

D

heat flow through C = heat flow through B + heat flow through D.

Text Solution

Verified by Experts

The correct Answer is:
A, C, D

Let width of each rod is d
`R_(1)=(1)/(8kd),R_(2)=(4)/(3kd)`
`R_(3)=(1)/(2kd),R_(4)=(4)/(5kd)`
`R_(5)=(1)/(24kd)`,
Correct choice is (a,c,d)
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Knowledge Check

  • Two slabs different materials with identical dimensions have their thermal condcutivities lambda_1 and lambda_2 respectively . When they are placed in contact with each other such that heat flows from one into the other ( placed in series ) , the equivalent thermal conductivity of the composite wall is given by

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  • Five rods of same dimensions are arranged as shown in the figure. They have thermal conductivities k_(1),k_(2),k_(3),k_(4) and k_(5) when points A and B are maintained at different temperatures. No heat flows through the central rod if

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