Magnetic Effects Of Current Question 20

Question 20 - 01 February - Shift 1

Find the magnetic field at the point $P$ in figure. The curved portion is a semicircle connected to two long straight wires.

(1) $\frac{\mu_0 i}{2 r}(1+\frac{2}{\pi})$

(2) $\frac{\mu_0 i}{2 r}(1+\frac{1}{\pi})$

(3) $\frac{\mu_0 i}{2 r}(\frac{1}{2}+\frac{1}{2 \pi})$

(4) $\frac{\mu_0 i}{2 r}(\frac{1}{2}+\frac{1}{\pi})$

Show Answer

Answer: (3)

Solution:

Formula: Magnetic field due to circular loop, Magnetic field due to a straight wire

$B_P=(\frac{\mu_0 i}{4 r}+\frac{\mu_0 i}{4 \pi r})=\frac{\mu_0 i}{2 r}(\frac{1}{2}+\frac{1}{2 \pi})$