Question 179: Electromagnetic Induction

Question

A circular coil of radius 10 cm is placed in a
uniform magnetic field of 3.0 $$ 	imes $$ 10
–5
T with its
plane perpendicular to the field initially. It is
rotated at constant angular speed about an
axis along the diameter of coil and
perpendicular to magnetic field so that it
undergoes half of rotation in 0.2 s. The
maximum value of EMF induced (in $$\mu $$V) in the
coil will be close to the integer _______.

Accepted Answer

At any time
flux $$\phi $$ = BA cos $$\omega t$$
|emf| = $$\left| {{{d\phi } \over {dt}}} ight|$$ = BA$$\omega$$ sin $$\omega t$$
|emf|
max
= BA$$\omega$$ = BA$${{2\pi } \over T}$$
= $${{3 	imes {{10}^{ - 5}} 	imes \pi  	imes {{\left( {0.1} ight)}^2} 	imes 2\pi } \over {0.4}}$$
= 15 $$ 	imes $$ 10
-6
= 15 $$\mu $$V

Electromagnetic Induction

Integer / Numeric Answer Type