Two insulated metal bars each of length 5 cm and rectangular cross section with sides 2 cm and 3 cm are wedged between two walls, one held at `100^@C` and the other at `0^@C`. The bars are made of lead and silver. `K_(pb)=350 W//mK,K_(Ag)=425 W//mK`. Equevalent thermal resistence of the two bar system isA. `0.1(K)/(W)`B. `0.23(K)/(W)`C. `0.19(W)/(W)`D. `0.42(K)/(W)`

Two insulated metal bars each of length 5 cm and rectangular cross se

1.	Two insulated metal bars each of length 5 cm and rectangular cross section with sides 2 cm and 3 cm are wedged between two walls, one held at `100^@C` and the other at `0^@C`. The bars are made of lead and silver. `K_(pb)=350 W//mK,K_(Ag)=425 W//mK`. Equevalent thermal resistence of the two bar system isA. `0.1(K)/(W)`B. `0.23(K)/(W)`C. `0.19(W)/(W)`D. `0.42(K)/(W)`
Answer» Correct Answer - A `(1)/(R_(eq))=(1)/(R_(pb))+(1)/(R_(Ag))=(21)/(5)+(51)/(10)` `=(42+51)/(10)=(93)/(10)` `R_(eq)=(10)/(93)=0.107Wcong0.1(K)/(W)`

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