
Two resistances and are connected in series with a battery of volt. The voltage across the resistance is measured using a voltmeter having a resistance of . Find the reading in the voltmeter.



Important Questions on Magnetic Effect of Electric Current



A galvanometer has a 50 division scale. Battery has no internal resistance. It is found that there is deflection of 40 divisions when Deflection becomes 20 divisions when resistance taken from resistance box is 4900 Ω. Then we can conclude :
Note: This question is awarded as the bonus. Now the question is corrected.

The galvanometer deflection, when key is closed but is open, equals (see figure). On closing also and adjusting to the deflection in galvanometer becomes The resistance of the galvanometer is, then, given by [Neglect the internal resistance of battery]:








Higher the range, greater is the resistance of ammeter.
To increase the range of ammeter, additional shunt needs to be used across it.










