Electromagnetic Induction problems
Faraday’s Law
1. (a) A coil of radius 20
cm consisting of 20 turns is held 2 meters above the south
end of a magnet. If the
coil is dropped, determine the average induced EMF
(voltage) once the loop
hits the magnet if the field strength at the 2 m height
is 0.005 T, and is 0.01 T
at the surface of the magnet.
(b) What is the direction
of the induced current, as seen from above the coil?
2..
A square loop of copper
coil 10 cm on each side is in static magnetic field of
0.005 T perpendicular to
the loop. The coil is deformed into a circle having the
same circumference as the
square loop. If this shape-change occurs in 5 seconds,
and the coil has a
resistance of 1 , determine the induced current in the coil.
3. A 100 turn conducting
circular coil of radius 1 cm is placed in a magnetic field
of variable.
3. A 100 turn conducting
circular coil of radius 1 cm is placed in a magnetic field
of variable strength B(t) = 0.01t + 0.01 Tesla,
which is perpendicular to the
plane of the loop. Determine the induced EMF.
Lenz’s Law
When an emf is generated by a change in
magnetic flux according to Faraday's Law, the polarity or direction of the
induced emf is such that it produces a current whose magnetic field opposes the
change which produces it.
