JEE Mains · Physics · STD 12 - Moving charges and magnetism
- JEE Mains 2026
- Easy
- MCQ
A moving coil galvanometer of resistance \(100 \Omega\) shows a full scale deflection for a current of 1 mA . The value of resistance required to convert this galvanometer into an ammeter, showing full scale deflection for a current of 5 mA , is _________ \(\Omega\)
Pick an option to check your answer.
Answer & Solution
Correct Answer
(A) 25
Step-by-step Solution
Detailed explanation
\(G =100 \Omega\)
\(i _{ g }=1 mA\)
\(i =5 mA\)
\(r_s=\frac{G}{\left(\frac{i}{i_g}-1\right)}\)
\(=\frac{100}{\left(\frac{5}{1}-1\right)}=25 \Omega\)
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