In the given circuit, the voltmeter  records 5 volts. The resistance of the voltmeter in ohms is

Options

A. 200
B. 100
C. 10
D. 50

Answer

b

Explanation

The resultant resistance of given circuit is`R_(result)=(Rxx100)/(R+100)+50`
`=(150R+5000)/(R+100)`
`i=(10V)/((150R+5000)/(R+100))`
The voltage across `AB = i x` resistance across AB
`V.=(10v)/((150R+5000)/(r+100))xx(Rxx100)/(R+100)`
`5=(10)/(150R+5000)xxRxx100`[Give V.=5V]
`implies75R+2500=100Rimplies25=2500impliesR=100Omega`