Question

Figure shows a square loop made from a uniform wire. Find the magnetic field at the center of square if a battery is connected between points $\text{A}$ and $\text{C}$.

• A. Zero
• B. ${\mu }_{0}I$
• C. $\frac{{\mu }_{0}I}{2}$
• D. $\frac{{\mu }_{0}I}{4}$

Answer 1

The correct option is A Zero


From the diagram, we can see that both part $\text{A-B-C}$ and $\text{A-D-C}$ are of same length so both have same amount of resistance means same current $I/2$ will flow though them.

As result magnetic field due to $\text{A-B-C}$ will be cancelled by $\text{A-D-C}$ at the center because of same magnitude but opposite direction.

i.e. $\overrightarrow{B_{net}}=0$

So, option $\left(a\right)$ is correct answer.