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`. Total thermal current through the two bar system isA. 210 WB. 420 WC. 510 WD. 930 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`. Total thermal current through the two bar system isA. 210 WB. 420 WC. 510 WD. 930 W
Answer» Correct Answer - D Resistance of silver bar `R_(Ag)=(l_Ag))/(K_(Ag)A_(Ag))=(5xx10^-2)/(425xx6xx10^-4)` `=(100)/(85xx6)=(20)/(17xx6)=(10)/(51)(K)/(W)` Thermal current through silver bar `I_(Ag)=(DeltaT)/(R_(Ag))=(100xx51)/(10)=510W` Total thermal current `I_(pb)+I_(Ag)=930W`

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