Current Electricity

Related Questions

• A potentiometer having the potential gradient of 2 mV/cm is used to measure the difference of potential across a resistance of 10 ohm. If a length of 50 cm of the potentiometer wire is required to get the null point, the current passing through the 10 ohm resistor is (in mA)

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• A 36 $\Omega$ galvanometer is shunted by resistance of 4$\Omega$. The percentage of the total current, which passes through the galvanometer is

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• Two bulbs of 500 watt and 200 watt are manufactured to operate on 220 volt line. The ratio of heat produced in 500 W and 200 W, in two cases, when firstly they are joined in parallel and secondly in series, will be

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• Some electric bulbs are connected in series across a 220 V supply in a room. If one bulb is fused then remaining bulbs are connected again in series across the same supply. The illumination in the room will

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• There is a current of 20 amperes in a copper wire of ${10^{ - 6}}$ square metre area of cross-section. If the number of free electrons per cubic metre is ${10^{29}}$, then the drift velocity is

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