An ammeter and a voltmeter are joined in sereis to a cell. Their readings are `A` and `V` respectively. If a resistance is now joinding parallel with the voltmeter. Then

Options

A. both `A` and `V `will increase
B. both and `V` will decreases
C. `A` will decrease, `V` will increase
D. `A` will increase, `V` will decrease

Answer

D

Explanation

Net resistance will decrease by increasing the parallel resistors. Therefore, main current `i` will increase, further,
`(PD)_("Voltmeter")=V_("Total")-(PD)_("Ammeter")`
`=V_("Total")-i("resistance of ammeter")`
Since i has increased. Hence, `PD` across voltmeter will decrease.