JEE Mains · Physics · STD 12 - Moving charges and magnetism
- JEE Mains 2019
- Medium
- MCQ
A current loop, having two circular arcs joined by two radial lines is shown in the figure. It carries a current of \(10\, A\). The magnetic field at point \(O\) will be close to
Pick an option to check your answer.
Answer & Solution
Correct Answer
(D) \(1.0 \times {10^{ - 5}}\,T\)
Step-by-step Solution
Detailed explanation
Magnetic field at clentre of an area subtending angle \(\theta\) at the centre \(\frac{\mu_{0} I}{4 \pi r} \theta\)
\(B=\left(\frac{\mu_{0}}{4 \pi}\right) \times 10\left(\frac{1}{3 \times 10^{-2}}-\frac{1}{5 \times 10^{-2}}\right) \frac{\pi}{4}\)
\(\quad=B=\frac{\pi}{30} \times 10^{-4}=\frac{\pi}{3} \times 10^{-5} \approx 10^{-5}\)
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