Current Electricity

Related Questions

• In a hydrogen discharge tube it is observed that through a given cross-section $3.13 \times 10^{15}$ electrons are moving from right to left and $3.12 \times 10^{15}$ protons are moving from left to right. What is the electric current in the discharge tube and what is its direction

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• The resistivity of iron is $1 \times {10^{ - 7}}\,ohm - m$. The resistance of a iron wire of particular length and thickness is 1 ohm. If the length and the diameter of wire both are doubled, then the resistivity in $ohm - m$ will be

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• In a potentiometer circuit there is a cell of e.m.f.2 volt, a resistance of 5 ohm and a wire of uniform thickness of length 1000 cm and resistance 15 ohm. The potential gradient in the wire is

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• A resistance of $4\,\Omega $ and a wire of length 5 metres and resistance $5\,\Omega $ are joined in series and connected to a cell of e.m.f. 10 V and internal resistance $1\,\Omega $. A parallel combination of two identical cells is balanced across 300 cm of the wire. The e.m.f.E of each cell is

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• Three resistances, each of 1 ohm, are joined in parallel. Three such combinations are put in series, then the resultant resistance will be

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