Question
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(a) 1 ohm(b) 0.2 ohm(c) 2.5 ohm(d) 0.4 ohm
       

Answer

(d) 0.4 ohm

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