JEE Mains · Physics · STD 12 - 4. Moving charges and magnetism
Find the magnetic field at the point \(P\) in figure. The curved portion is a semicircle connected to two long straight wires.
- A \(\frac{\mu_0 i}{2 r}\left(1+\frac{2}{\pi}\right)\)
- B \(\frac{\mu_0 i}{2 r}\left(1+\frac{1}{\pi}\right)\)
- C \(\frac{\mu_0 i}{2 r}\left(\frac{1}{2}+\frac{1}{2 \pi}\right)\)
- D \(\frac{\mu_0 i}{2 r}\left(\frac{1}{2}+\frac{1}{\pi}\right)\)
Answer & Solution
Correct Answer
(C) \(\frac{\mu_0 i}{2 r}\left(\frac{1}{2}+\frac{1}{2 \pi}\right)\)
Step-by-step Solution
Detailed explanation
\(B_{ P }=\left(\frac{\mu_0 i}{4 r}+\frac{\mu_0 i}{4 \pi r}\right)=\frac{\mu_0 i}{2 r}\left(\frac{1}{2}+\frac{1}{2 \pi}\right)\)
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