Current through a voltmeter with internal resistance

AI Thread Summary
The discussion centers on calculating the current through a voltmeter with internal resistance when measuring voltage across a resistor in a circuit. The equivalent resistance of the 5 ohm resistor and the voltmeter's 3 ohm resistance is determined to be approximately 1.815 ohms, leading to a voltage reading of 4.83 V. There is confusion about whether the current through the voltmeter is the same as the total circuit current or just through its internal resistance. The total current through the circuit is calculated as 10 V divided by the total resistance of 2 ohms plus the equivalent resistance. The calculations for both scenarios are being verified to clarify the correct current measurement.
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Homework Statement


You have a power supply of 10 V. It is connected in series to a 2 ohm resistor and a 5 ohm resistor.

You take the voltage across the 5 ohm resistor with a voltmeter that has an internal resistance of 3 ohms. What is the current through the voltmeter?

Homework Equations


The Attempt at a Solution


So I figured out the equivalent resistance of 5 ohms and 3 ohms is 1.815 ohms. Then the voltage across that is 4.83 V, which is the voltage read by the voltmeter.

Is the current going through the voltmeter just the same as the current going through the entire circuit? (So 10/(2 + 1.815))

Or is it the current just through the voltmeter's 3 ohm internal resistance? (Which I found to be 1.64 A)?
 
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Equivalent resistance R = 5*3/8 = ? Check this calculation.
 
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