JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
Magnetic fields at two points on the axis of a circular coil at a distance of \(0.05\, m\) and \(0.2\, m\) from the centre are in the ratio \(8: 1.\) The radius of coil is .......... \(m\)
- A \(0.2\)
- B \(0.1\)
- C \(0.15\)
- D \(1.0\)
Answer & Solution
Correct Answer
(B) \(0.1\)
Step-by-step Solution
Detailed explanation
We know, the magnetic field on the axis of a current carrying circular ring is given by \(B =\frac{\mu_{0}}{4 \pi} \frac{2 NIA }{\left( R ^{2}+ x ^{2}\right)^{3 / 2}}\)…
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