Question

A galvanometer of resistance $25 \Omega$ gives full scale deflection for a current of 10 milliampere, is to be changed into a voltmeter of range 100 V by connecting a resistance of ‘R’ in series with galvanometer. The value of resistance R in $\Omega$ is

• A. 10000
• B. 10025
• C. 975
• D. 9975

Answer 1

Answer: (D)

9975

Answer 2

$R = \frac { V } { i _ { g } } - G = \frac { 100 } { 10 \times 10 ^ { - 3 } } - 25 = 9975 \Omega$