Question

Question 3.7: A silver wire has a resistance of 2.1 Ω at 27.5 °C, and a resistance of 2.7 Ω at 100 °C. Determine the temperature coefficient of resistivity of silver.

Class 12 - Physics - Current Electricity Current Electricity Page-127

Answer 1

Given, $T_0=27.5^{\circ}C,R_0=2.1 ohm, T=100^{\circ}C,and, R=2.7ohm$

using the relation , $R=R_0[1+\alpha(T-T_0)]$, where $\alpha$ is the coefficient of resistance .
$so,\alpha=\frac{R-R_0}{R_0(T-T_0)}\\\\=\frac{2.7-2.1}{2.1(100-27.5)}\\\\=\frac{0.6}{152.25}\\\\=3.94\times10^{-3}/^{\circ}C$

hence, coefficient of resistance of silver is 3.94 × 10^-3 / °C

Answer 2

Explanation:

Hllo friends..

Here your answer..

Given=Temperature, T1 = 27.5°C Resistance of the silver wire at T1, R1 = 2.1 Ω Temperature, T2 = 100°C Resistance of the silver wire at T2, R2 = 2.7 Ω ..

Temperature coefficient of silver = α It is related with temperature and resistance ..

Temperature coefficient of resistivity is:

Temperature coefficient of resistivity is:α=R2−R1/R1(T2−T2)

=0.0039degreeC^−1

Therefore, the temperature coefficient of silver is 0.0039°C - 1.

Hope it helps you