Q. 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) $111\Omega$
Explanation
(d) By using $\frac{i}{i_{g}} = 1 + \frac{G}{S}$
$\Rightarrow \frac{i}{100 \times 10^{- 3}} = 1 + \frac{1000}{S} \Rightarrow S = \frac{1000}{9} = 111\Omega$
Reviewed by Dr. Abubacker
Physics Educator & NEET/JEE Specialist
Ph.D. in Physics with 19+ years of teaching experience.