Question

An ammeter of resistance R gives a full-scale deflection when a current of 2 A passes through it. If it is measured with a maximum current of 10 A, the required shunt is ______.

पर्याय

• R

• ${\displaystyle \frac{\text{R}}{2}}$

• ${\displaystyle \frac{\text{R}}{4}}$

• 2R

Answer 1

An ammeter of resistance R gives a full-scale deflection when a current of 2 A passes through it. If it is measured with a maximum current of 10 A, the required shunt is ${\displaystyle \underline{\frac{\text{R}}{4}}}$.

Explanation:

Given, l = 2A, l_max = 10A

Since, shunt resistance, S = ${\displaystyle \frac{lR}{l_{\text{max}}-l}}$

= ${\displaystyle \frac{2R}{10-2}=\frac{2}{8}R=\frac{1}{4}R}$