JEE Mains · Physics · STD 12 - Moving charges and magnetism
- JEE Mains 2020
- Hard
- MCQ
Magnitude of magnetic field (in \(SI\) units) at the centre of a hexagonal shape coil of side \(10\, cm\), \(50\) turns and carrying current \(I\) (Ampere) in units of \(\frac{\mu_{0} I}{\pi}\) is
Pick an option to check your answer.
Answer & Solution
Correct Answer
(C) \(500 \sqrt{3}\)
Step-by-step Solution
Detailed explanation
\(B =\frac{6 \mu_{0} I }{4 \pi a \cos 30^{\circ}} \times 2 \sin 30^{\circ} \times 50\)
\(=\frac{\mu_{0} I}{\pi} \frac{150}{\sqrt{3} a }=\frac{50 \sqrt{3}}{0.1} \frac{\mu_{0} I}{\pi}\)
\(=500 \sqrt{3} \frac{\mu_{0} I}{\pi}\)

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