2026 Current ElectricityConversion of galvanometer to ammeter (shunt resistance) Easy Question 2 of 130 in Current Electricity

A galvanometer of resistance 100 $\Omega$ gives full scale deflection for a current of 1 mA. It is converted into an ammeter of range 0 - 10 A. The shunt required is:

A 0.01 $\Omega$
B 0.10 $\Omega$
C 0.001 $\Omega$
D 1.0 $\Omega$

The answer is A.

Solution

$R_g = 100\ \Omega$, $I_g = 1$ mA, I = 10 A $S = \frac{I_g R_g}{I - I_g} = \frac{10^{-3} \times 100}{10 - 10^{-3}}$ Since $I_g << I$, $I - I_g \approx I$ $S = 10^{-2} = 0.01\ \Omega$

Current Electricity in past papers

130 questions from this chapter have appeared across 27 exam years.