Question

A single turn circular coil is connected to a cell as shown in figure. Magnetic field at the centre $O$ of the coil is

• A. $\frac{2\pi l}{r}$
• B. $2\pi lr$
• C. Zero
• D. $\frac{l}{2\pi r}$
• E. $\frac{1}{\pi r}$

Answer 1

Answer: (C)

Zero

Since, the current flowing through the circuit gets equally divided in both the semicircle of the coil. So, the magnetic fields produced at $O$ by both the semicircles are equal and opposite. So, the net magnetic field at the centre $O$ of the coil is zero.