Question

A voltmeter of resistance $1000\,\Omega$ gives full scale deflection when a current of $100\,mA$ flows through it. The shunt resistance required across it to enable it to be used as an ammeter reading $1\,A$ at full scale deflection is

• A. $10000\,\Omega$
• B. $9000\,\Omega$
• C. $222\,\Omega$
• D. $111\,\Omega$

Answer 1

Answer: (D)

$111\,\Omega$

Answer 2

By using $\frac{i}{i_{g}}=1+\frac{1000}{S}$ $\frac{i}{100\times 10^{-3}}=1+\frac{1000}{S}$ $\Rightarrow S=\frac{1000}{9}$ $=111\,\Omega$