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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• Two electric bulbs (60W and 100W respectively) are connected in series. The current passing through them is

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• The potential difference in open circuit for a cell is 2.2 volts. When a 4 ohm resistor is connected between its two electrodes the potential difference becomes 2 volts. The internal resistance of the cell will be

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• The terminal potential difference of a cell when short-circuited is ($E$ = E.M.F. of the cell)

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• AB is a potentiometer wire of length 100 cm and its resistance is 10 ohms. It is connected in series with a resistance R = 40 ohms and a battery of e.m.f. 2 V and negligible internal resistance. If a source of unknown e.m.f.E is balanced by 40 cm length of the potentiometer wire, the value of E is

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