A silver wire has a resistance of 2.1 Omega a | vedclass

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(A) Given:Resistance at $T_0 = 27.5^{\circ} C$ is $R_0 = 2.1 \Omega$.Resistance at $T = 100^{\circ} C$ is $R = 2.7 \Omega$.The formula for temperature

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$3.9 	imes 10^{-3} {}^{\circ} C^{-1}$

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(A) Given:Resistance at $T_0 = 27.5^{\circ} C$ is $R_0 = 2.1 \Omega$.Resistance at $T = 100^{\circ} C$ is $R = 2.7 \Omega$.The formula for temperature dependence of resistance is $R = R_0[1 + \alpha(T - T_0)]$.Substituting the values:$2.7 = 2.1[1 + \alpha(100 - 27.5)]$$2.7 = 2.1[1 + \alpha(72.5)]$$\frac{2.7}{2.1} = 1 + \alpha(72.5)$$\frac{9}{7} = 1 + \alpha(72.5)$$\frac{9}{7} - 1 = \alpha(72.5)$$\frac{2}{7} = \alpha(72.5)$$\alpha = \frac{2}{7 	imes 72.5} = \frac{2}{507.5} \approx 0.00394 \approx 3.9 	imes 10^{-3} {}^{\circ} C^{-1}$.Thus,the correct option is $A$.

$A$ silver wire has a resistance of $2.1 \Omega$ at $27.5^{\circ} C$ and a resistance of $2.7 \Omega$ at $100^{\circ} C$. Then the temperature coefficient of the resistivity of silver will be . . . . . . .

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