Current Electricity

Related Questions

• A 50 ohm galvanometer gets full scale deflection when a current of 0.01 A passes through the coil. When it is converted to a 10 A ammeter, the shunt resistance is

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• Equal potentials are applied on an iron and copper wire of same length. In order to have the same current flow in the two wires, the ratio r (iron)/r (copper) of their radii must be (Given that specific resistance of iron = $1.0\times10^{-7}ohm–m$ and specific resistance of copper = $1.7\times10^{-8}ohm-m$)

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• A platinum resistance thermometer has a resistance of 50 ohm at $20^\circ C$. When dipped in a liquid the resistance becomes $76.8\,\Omega$. The temperature coefficient of resistance for platinum is $\alpha = 3.92 \times {10^{ - 3}}/^\circ C$. The temperature of the liquid is

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• In an electrolyte $3.2 \times {10^{18}}$ bivalent positive ions drift to the right per second while $3.6 \times {10^{18}}$ monovalent negative ions drift to the left per second. Then the current is

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• Two resistances ${R_1}$ and ${R_2}$ are joined as shown in the figure to two batteries of e.m.f.${E_1}$ and ${E_2}$. If ${E_2}$ is short-circuited, the current through ${R_1}$is

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