Question

An ammeter whose resistance is 180 $\Omega$ gives full scale deflection when curent is 2mA. The shunt required to convert into an ammeter reading 20 mA (in ohm)

• A. 18
• B. 20
• C. 0.1
• D. 10

Answer 1

The correct option is B 20

So $i_{g}G=S(i-i_g)$

$S=\frac{i_{g}G}{i-i_g}$

$S=\frac{2\times {10}^{-3}\times 180}{(20-2){10}^{-3}}$

=$\frac{2\times 180}{18}$

=$20\Omega$