Current Electricity

Related Questions

• A wire of radius r has resistance R. If it is stretched to a radius of $\frac{3r}{4}$, its resistance becomes

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• A potentiometer is used for the comparison of e.m.f. of two cells ${E_1}$ and ${E_2}$. For cell ${E_1}$ the no deflection point is obtained at 20$cm$ and for ${E_2}$ the no deflection point is obtained at 30$cm$. The ratio of their e.m.f.'s will be

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• Express which of the following setups can be used to verify Ohm’s law

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• A voltmeter having a resistance of 998 ohms is connected to a cell of e.m.f. 2 volt and internal resistance 2 ohm. The error in the measurement of e.m.f. will be

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• Equivalent resistance between the points A and B is (in $\Omega$)

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