A students connects an ammeter `A ` and a voltmeter `V` to measure a resistancer as shown in figure. If the voltmeter reads `20 V` and the ammeter reads `4A`, then `R` is

Options

A. Equal to `5 Omega`
B. Greater than `5 Omega`
C. Less than `5 Omega`
D. Greater or less than `5 Omega` depending upon the direction of current

Answer

C

Explanation

As the given ammeter and voltmeter are not considered ideal, we use:
`4(R + R_(A)) = 20`
`R = 5-R_(A), R_(A) to` Resistance of ammeter.