Join the Most Relevant JEE Main 2025 Test Series & get 99+ percentile! Join Now
Search any question & find its solution
Question: Answered & Verified by Expert
A galvanometer of resistance $25 \Omega$ shows a deflection of 5 divisions when a current of 2 mA is passed through it. If a shunt of $4 \Omega$ is connected and there are 20 divisions on the scale, then the range of the galvanometer is
PhysicsCurrent ElectricityJIPMERJIPMER 2016
Options:
  • A 1 A
  • B 58 A
  • C 58 mA
  • D 30 mA
Solution:
2144 Upvotes Verified Answer
The correct answer is: 58 mA
There are 20 divisions on scale. Initially, current for 20 divisions $=\frac{2 \times 20}{5}=8 \mathrm{~mA}$
$\begin{array}{ll}\therefore & I g=8 \mathrm{~mA} \\ \because & \frac{I g}{I}=\frac{S}{S+G}\end{array}$
$\begin{aligned} \Rightarrow \quad I & =\left(\frac{S+G}{S}\right) I_g \Rightarrow I=\left(\frac{4+25}{4}\right) \times 8 \\ & =29 \times 2=58 \mathrm{~mA}\end{aligned}$

Looking for more such questions to practice?

Download the MARKS App - The ultimate prep app for IIT JEE & NEET with chapter-wise PYQs, revision notes, formula sheets, custom tests & much more.