A galvanometer has a resistance of G ohm and range of V volt. Calculate the resistance to be used in seres with it to extend its range its renge to nV volt.

Options

A. `(n-1)G`
B. `G/(n-1)`
C. `nG`
D. `G/n`

Answer

A

Explanation

The value of high resistance (R ) that should be connected in series with the galvanometer of resistance G for converting it into a voltmeter of range 0 to V is given by `R=V/I_g-G and I_g=V/G` For increasing its range to nV, R should be charged to R'. So that `R'=(nV)/((V/G))-G therefore R'=nG-G=G(n-1)`.