Question

An ammeter and a voltmeter are joined in series to a cell. Their readings are A and V respectively. If a resistance is now joined in parallel with the voltmeter, 

(a) both A and V will increase 

(b) both A and V will decrease 

(c) A will decrease, V will increase 

(d) A will increase, V will decrease

Answer 1

Correct Answer is: (d) A will increase, V will decrease

When a resistance is joined in parallel with the voltmeter, the total resistance of the circuit decreases. Current will increase and ammeter reading will increase. The equivalent resistance across the voltmeter decreases and hence its reading will decrease.