Question

A plane of area A is placed in uniform magnetic field B with its normal making an angle of ${45}^{\circ }$ with the field. Which of the following statements is true about magnetic flux $\Phi$?

• A. $\Phi$ = BA
• B. $\Phi$ = 2BA
• C. $\Phi$ = BA/$\sqrt{2}$
• D. $\Phi$ = BA/2

Answer 1

The correct option is C $\Phi$ = BA/$\sqrt{2}$

Magnetic flux $\Phi$ is related to the magnetic field B and the effective area of the plane A as $\Phi$ = BAcos$\theta$

Given $\theta ={45}^{\circ }$, hence $\Phi$ = BA/$\sqrt{2}$.