Current Electricity

Related Questions

• Two wires ‘A’ and ‘B’ of the same material have their lengths in the ratio 1 : 2 and radii in the ratio 2 : 1. The two wires are connected in parallel across a battery. The ratio of the heat produced in ‘A’ to the heat produced in ‘B’ for the same time is

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• Dimensions of a block are $1\,cm \times 1\,cm \times 100\,cm$. If specific resistance of its material is $3 \times {10^{ - 7}}ohm - m$, then the resistance between the opposite rectangular faces is

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• Dimensions of a block are $1\,cm \times 1\,cm \times 100\,cm$. If specific resistance of its material is $3 \times {10^{ - 7}}ohm - m$, then the resistance between the square faces is

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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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• The resistance of 10 metre long potentiometer wire is 1ohm/meter. A cell of e.m.f.2.2 volts and a high resistance box are connected in series to this wire. The value of resistance taken from resistance box for getting potential gradient of 2.2 millivolt/metre will be

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