Question

A circular disc of radius $0.2$ meter is placed in a uniform magnetic field of $\frac{1}{\pi }$ $wb/m^2$ in such way that its axis makes an angle of ${60}^o$ with $\overrightarrow{B}$. The magnetic flux linked with the disc is?

• A. $0.08$ wb
• B. $0.01$ wb
• C. $0.02$ wb
• D. $0.06$ wb

Answer 1

Answer: (C)

$0.02$ wb

Here $B=\frac{1}{\pi }$ (Wb/m²)

$\theta =60⁰$

Area normal to the plane of the disc

= $\pi r^2\left(cos60⁰\right)=\frac{\pi r^2}{2}$

Flux = B x normal area

= $0.2\times \frac{0.2}{2}=0.02$Wb