Same mass of copper is drawn into 2 wires of 1 mm thick ad 3 mm thick. Two wires are connected in series and current is passed. Heat produced in the wires is the ratio ofA. `3:1`B. `9:1`C. `81:1`D. `1:81`

Same mass of copper is drawn into 2 wires of 1 mm thick ad 3 mm thick.

1.	Same mass of copper is drawn into 2 wires of 1 mm thick ad 3 mm thick. Two wires are connected in series and current is passed. Heat produced in the wires is the ratio ofA. `3:1`B. `9:1`C. `81:1`D. `1:81`
Answer» Correct Answer - C `Q=i^(2)Rt` `QalphaRalpha(1)/(A^(2))` when wire is stretched `(Q_(1))/(Q_(2))=(r_(2)^(4))/(r_(1)^(4))=(3^(4))/(1^(4))=81.1`

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Same mass of copper is drawn into 2 wires of 1 mm thick ad 3 mm thick. Two wires are connected in series and current is passed. Heat produced in the wires is the ratio ofA. `3:1`B. `9:1`C. `81:1`D. `1:81`

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