A wire has a resistance of 5.5 Ω at 19^oC and 21.5 Ω at 200^oC. Find the temperature coefficient of resistivity(α) of the material.(a) 0.016 ^oC^-1(b) 0.160 ^oC^-1(c) 1.600 ^oC^-1(d) 16.00 ^oC^-1I have been asked this question in an international level competition.Enquiry is from Current Electricity topic in portion Current Electricity of Physics – Class 12

A wire has a resistance of 5.5 Ω at 19^oC and 21.5 Ω at 200^oC. Find

1.	A wire has a resistance of 5.5 Ω at 19^oC and 21.5 Ω at 200^oC. Find the temperature coefficient of resistivity(α) of the material.(a) 0.016 ^oC^-1(b) 0.160 ^oC^-1(c) 1.600 ^oC^-1(d) 16.00 ^oC^-1I have been asked this question in an international level competition.Enquiry is from Current Electricity topic in portion Current Electricity of Physics – Class 12
Answer» RIGHT CHOICE is (a) 0.016 ^oC^-1 Explanation: TEMPERATURE COEFFICIENT α=\(\FRAC {(R_2-R_1)}{R_2(T_2-T_1)}\). α = \(\frac {(21.5-5.5)}{(5.5(200-19))}\) = 0.01607 ^oC^-1.

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