Question

In the given circuit the voltmeter records 5 volts. what is the resistance of the voltmeter in ohm

Answer 1

since voltmeter reads 5V that means v across 100ohm resistor is 5v

let current I is flowing across the 100ohm resistor

so I=V/R…. 5/100= .05 A

and please look closely the circuit is open i.e the current is just circulating in the loop… therefore I across the voltmeter is also .05A and v is already known i.e 5 v

le voltmeter resistance R’

IR’=5

R’=5/.05

which gives R’=100 ohms