COMEDK2014PhysicsCurrent Electricity
The resistance of a galvanometer is 2.5 and it requires 50 ~mA for full scale deflection. The value of shunt resistance required to convert it into an ammeter of range 0 to 5 ~A is
Options
- A2.5 10⁻²
- B0.25 10⁻²
- C0.025 10⁻²
- D0.0025 10⁻²
Correct answer
A. 2.5 10⁻²
Step-by-step solution
Given, resistance of galvanometer, R_ g =2.5 Full scale deflection current, aligned I_ g &=50 ~mA =50 10⁻³ ~A &=0.05 ~A aligned Range of galvanometer is (0-5) A I=5 ~A If R_ s be the shunt resistance, then aligned (I-I_ g ) R_ s =I_ g R_ g R_ s &= I_ g R_ g I-I_ g &= 0.05 2.5 5-0.05 &=0.025 =25 10⁻² aligned