A composite metal bar of uniform section is made up of length 25 cm of copper- 10 cm of nickel and 15 cm of aluminium- Each part being in perfect thermal contact with the adjoining part- The copper end of the composite rod is maintained at 100- C and the aluminium end at 0- C- The whole rod is covered with belt so that there is no heat loss occurs at the sides- If K Ca -2 K Al- and K Al -3 K Ni- then what will be the temperatures of Cu - Ni and Ni- Al junctions respectivelyA- 50- C and 30- CB- 30- C and 50- CC- 78-20 C and 26-080 CD- 83-33- C and 20- C

The correct option is C In series rate of flow of heat is constatnt 100 θ_1/25/6KA=θ_1 θ_2/10/KA=θ_2 0/15/3KA Solving θ_1=78.2^0c,θ_2=26.08^0c ...

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Byju's Answer

Standard XII

Physics

Capacitance of a Random Conductor

A composite m...

Question

A composite metal bar of uniform section is made up of length 25 cm of copper, 10 cm of nickel and 15 cm of aluminium. Each part being in perfect thermal contact with the adjoining part. The copper end of the composite rod is maintained at $100^{\circ} C$ and the aluminium end at $0^{\circ} C$ . The whole rod is covered with belt so that there is no heat loss occurs at the sides. If $K_{C a} = 2 K_{A l}$ , and $K_{A l} = 3 K_{N i}$ , then what will be the temperatures of Cu - Ni and Ni- Al junctions respectively

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Solution

The correct option is A

$I n s e r i e s r a t e o f f l o w o f h e a t i s c o n s t a t n t \frac{100 - θ_{1}}{\frac{25}{6 K A}} = \frac{θ_{1} - θ_{2}}{\frac{10}{K A}} = \frac{θ_{2} - 0}{\frac{15}{3 K A}} S o l v i n g θ_{1} = {78.2}^{0} c, θ_{2} = {26.08}^{0} c$

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The correct option is A In series rate of flow of heat is constatnt100−θ1256KA=θ1−θ210KA=θ2−0153KASolvingθ1=78.20c,θ2=26.080c

The correct option is A

$I n s e r i e s r a t e o f f l o w o f h e a t i s c o n s t a t n t \frac{100 - θ_{1}}{\frac{25}{6 K A}} = \frac{θ_{1} - θ_{2}}{\frac{10}{K A}} = \frac{θ_{2} - 0}{\frac{15}{3 K A}} S o l v i n g θ_{1} = {78.2}^{0} c, θ_{2} = {26.08}^{0} c$