Question

If the reading of voltmeter v1 is 40 volts what is the reading of voltmeter v 2

Answer 1

Understand that the Voltmeter ideally, has infinite resistance and is considered an open circuit….. Now, Since each branch has 20E the current will be flowing through them equally…Since 2A is injected into the circuit, each branch receives 1A.

This means at the +ve lead of the voltmeter there is -4V(Since that is the lead of the resistance through which current leaves, and at the -ve lead there is a -16V(Sign convention logic, same as above)… So the Voltage across the voltmeter is the DIFFERENCE between the two; ie

Voltage read=(Voltage at +ve lead) - (Voltage at -ve lead)

V=(-4)-(-16) = 16–4=12V.

Answer 2

12v

Hope you understand... :