Current Electricity

Related Questions

• In a potentiometer experiment the balancing with a cell is at length 240 cm. On shunting the cell with a resistance of 2 $\Omega$, the balancing length becomes 120 cm. The internal resistance of the cell is

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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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• A potential difference of V is applied at the ends of a copper wire of length l and diameter d. On doubling only d, drift velocity

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• Two identical heaters rated 220 volt, 1000 watt are placed in series with each other across 220 volt lines. If resistance do not change with temperature, then the combined power is

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• For a cell of e.m.f. 2V, a balance is obtained for 50 cm of the potentiometer wire. If the cell is shunted by a $2\,\Omega $ resistor and the balance is obtained across 40 cm of the wire, then the internal resistance of the cell is

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