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)=425W//mK`. Thermal corrent through lead bar 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)=425W//mK`. Thermal corrent through lead bar isA. 210 WB. 420 WC. 510 WD. 930 W
Answer» Correct Answer - B Resistance of lead bar `R_(pb)=(l_(pb))/(K_(pb)A_(pb))=(5xx10^-2)/(350xx6xx10^-4)` `=(10)/(21)=(5)/(21)(K)/(W)` Thermal current through lead bar `I_(pb)=(DeltaT)/(R_pb))=(100xx21)/(5)=420W`

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