In a potentiometer experiment for measuring the emf of a cell, the null point is at 480 cm when we have a resistor in series with the cell and galvanometer. If the series resistances is reduced to half, the null point will be at |
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a) |
120 cm |
b) |
240 cm |
c) |
480 cm |
d) |
600 cm |

In a potentiometer experiment for measuring the emf of a cell, the null point is at 480 cm when we have a resistor in series with the cell and galvanometer. If the series resistances is reduced to half, the null point will be at |
|||||||

a) |
120 cm |
b) |
240 cm |
c) |
480 cm |
d) |
600 cm |

1 Answer

127 votes

At null point, no current flows through galvanometer. Therefore, the resistance connected in series with galvanometer, at null point position will be in effective. Thus, null point is obtained on potentiometer wire at the original position after the removal wire at the original position after the removal of series resistance from galvanometer |

127 votes

127