If a varying magnetic Field is cut by a coil, an E.M.F. will be induced on its terminals and electric current will flow.
The size of the E.M.F induced depends on the cutting rate of magnetic field lines
To increase the cutting rate :
1. Increase the number of turns of the coil
2. Increase the magnetic flux density of the magnet
3. Increase the speed of the magnet
The current induced will be in such a direction opposing the change causing it.
The current in the coil creates a magnetic field opposing the motion of the magnet
2 circuits with 2 different coils, one of them is connected to an AC current, the other will have E.M.F. induced into
it
Adding a soft iron bar into the 2 coils increases the E.M.F. Induced
B
=
ϕ
A
ϕ
=
BA
B
Magnetic Flux Density in Tesla
A
Area
⊥
to the field
ϕ
Measured in weber (
Wb
) or
Tm
2
Magnetic flux linkage (for a solenoid)
Electromagnetic Induction
Lenz's Law
Magnetic Flux
ϕ
