A galvanometer with a scale divided into 150 equal division has a senstivity of 10 divisions per milliampere and a voltage senstivity of 2 divisions per milivolt. What is the resistance of the galvanometer ?

Options

A. `2.5 Omega`
B. `5 Omega`
C. `7.5 Omega`
D. `10 Omega`

Answer

B

Explanation

maximum current`I_g/I=I/3=S/(S+R) therefore 3S -S+R therefore S=R/2Omega` Maximum voltage that can be read is `V=(150)/(2"div"//mA)=75mA therefore R=v_(max)/I_(max)=(75 xx 10^(-3))/(15 xx 10^(-3))5Omega`.