JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
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 _________ \(\Omega\)
- A 25
- B 10
- C 0.5
- D 2.5
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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