question_answer

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, then:

A)  A will decrease, V will increase

B)  A will increase, V will decrease

C)  both A and V will increase

D)  both A and V will increase

Correct Answer: B

Solution :

Equivalent circuit in Wheatstone bridge\[I=0\] in PQ. \[{{R}_{eq}}=\frac{2R\times 2R}{4R}=R\]