Question

A circular disc of radius 0.2 m is placed in a uniform magnetic field of induction$\left( \frac { 1 } { \pi } \right)$ Wb m-2 in such a way that its axis makes an angle of 60° with . The magnetic flux linked with the disc is

• A. 0.02 Wb
• B. 0.06 Wb
• C. 0.08 Wb
• D. 0.01 Wb

Answer 1

Answer: (A)

0.02 Wb

Answer 2

Here , $\mathrm { r } = 0.2 \mathrm {~m} , \mathrm {~B} = \frac { 1 } { \pi } \mathrm { Wbm } ^ { - 2 }$

$\theta = 60 ^ { \circ }$

$\therefore$Magnetic flux,

$\phi = \mathrm { BA } \cos \theta = \mathrm { B } \left( \pi \mathrm { r } ^ { 2 } \right) \cos \theta$

$= \frac { 1 } { \pi } \pi ( 0.2 ) ^ { 2 } \cos 60 ^ { \circ } = 0.02 \mathrm {~Wb}$