A voltmeter which can measure 2 V isconstructed by using a galvanometer of resistance `12 Omega` and that produces maximum deflection for the current of 2mA. Then the resistance R is

Options

A. `888 Omega`
B. `988 Omega`
C. `898 Omega`
D. `999 Omega`

Answer

B

Explanation

`R=V/I_(g)-G`
Putting `V=2 V, I_(g)= 2 mA= 2 xx 10^(-3) A, G=12 Omega`.
`therefore R=2/(2 xx 10^(-3)) -12 = 1000 -12=988 Omega`