How Does a Voltmeter Measure Voltage in a Circuit with Internal Resistance?

[viperassasin]

Homework Statement

A voltmeter with resistance R_V is connected across the terminals of a battery of emf EMF and internal resistance r. Find the potential difference V_meter measured by the voltmeter.

Homework Equations

v=IR Vab= Va -Vb

The Attempt at a Solution

tried using equations with epsolon.

 

[Feldoh]

Just go in a loop around the circuit, and re-arrange for Vf-Vi