JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
A galvanometer having a coil resistance of \(100\ \Omega\). gives a full scale deflection, when a currect of \(I\ mA\) is passed through it. The value of the resistance, which can convert this galvanometer into ammeter giving a full scale deflection for a current of \(10\ A\), is :......\(Ω\)
- A \(0.1\)
- B \(3\)
- C \(0.01\)
- D \(2 \)
Answer & Solution
Correct Answer
(C) \(0.01\)
Step-by-step Solution
Detailed explanation
\(\lg \mathrm{G}=(\mathrm{I}-\mathrm{Ig}) \mathrm{s}\) \(\therefore 10^{-3} \times 100=\left(10-10^{-3}\right) \times \mathrm{S}\) \(\therefore \mathrm{S} \approx 0.01 \,\Omega\)
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