Voltmeter question .

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Voltmeter question...

Homework Statement

A student connects an Ammeter A and a Voltmeter V to measure a Resistance R as shown in attached diagram...If the Voltmeter reads 20 V and the ammeter reads 4A then R is
1. equal to5 ohm
2. Greater than 5 ohm
3. Less than 5 ohm
4. Greater than or less than 5 ohm dpending upon the direction of current

Homework Equations

The Attempt at a Solution

My answer is number 3. Less than 5ohm But answer is 2. Gretaer than 5 ohm
...Assuming voltmeter and ammeter are non ideal the PD is still exactly 20V and current is exactly 4A now applying V=iR we get net resistance to be 5ohm but since ammeter has some resistance and total resistance is 5ohm the value of R should be less than 5ohm...This is my reasoning...

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