Question

Assertion :The magnetic field at the centre of the circular coil in the following figure due to the currents $I_1$ and $I_2$ is zero, Reason: $I_1=I_2$ implies that the fields due to the current $I_1$ and $I_2$ will be balanced.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Both Assertion and Reason are incorrect

Answer 1

The correct option is D Both Assertion and Reason are incorrect

$\frac{I_1}{I_2}=\frac{2\pi -\theta }{\theta }\Rightarrow I_1\theta =I_2(2\pi -\theta )................\left(1\right)$

$B_I=\frac{\theta }{2\pi }\cdot \frac{{\mu }_0{I}_1}{2R}$ and

$B_2=\frac{2\pi -\theta }{2\pi }\cdot \frac{{\mu }_0{I}_2}{2R}$

Using $\left(1\right)$, we get $B_1=B_2$