Identify the temperature at which the resistance of copper would be double of its resistance at ^oC. Given α (temperature coefficient of resistivity) for copper=3.9 x 10^-3 ^oC^-1.(a) 125^oC(b) 256^oC(c) 1080^oC(d) 273^oCThe question was posed to me in an international level competition.This is a very interesting question from Current Electricity topic in portion Current Electricity of Physics – Class 12

Identify the temperature at which the resistance of copper would be do

1.	Identify the temperature at which the resistance of copper would be double of its resistance at ^oC. Given α (temperature coefficient of resistivity) for copper=3.9 x 10^-3 ^oC^-1.(a) 125^oC(b) 256^oC(c) 1080^oC(d) 273^oCThe question was posed to me in an international level competition.This is a very interesting question from Current Electricity topic in portion Current Electricity of Physics – Class 12
Answer» The CORRECT choice is (b) 256^oC Easy EXPLANATION: α=\(\frac {(R_2-R_1)}{R_2(T_2-T_1)}\). α=\(\frac {(2R_0-R_0)}{R_0(T-0)} = \frac {1}{T}\). T=\(\frac {1}{\alpha}\) = \(\frac {1}{3.9}\) X 10^-3 ^oC^-1 = 256^oC. Therefore, the REQUIRED temperature is 256^oC.

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