Question

An ammeter reads upto 1 ampere. Its internal resistance is 0.81 ohm. To increase the rangeto 10 A the value of the required shunt is

• A. 0.03 $\Omega$
• B. 0.3 $\Omega$
• C. 0.9 $\Omega$
• D. 0.09 $\Omega$

Answer 1

The correct option is D 0.09 $\Omega$

$S=\frac{I_{g}G}{I-I_g}=\frac{1\times 0.81}{10-1}=0.09\Omega$