Copyright © Michael Richmond.
This work is licensed under a Creative Commons License.
Magnetic Induction
First, finish up magnetic fields created by currents
- A solenoid is a cylindrical coil of wire. It creates a relatively
uniform magnetic field in its interior, of strength
B = mu * n * I
where mu is the magnetic permeability of free space,
n is the number of turns of wire per meter, and
I is the current through the wire.
Okay, now on to magnetic induction
- Under some circumstances, a magnetic field can create an
electric voltage, or an electric current. This phenomenon
is called magnetic induction. It always involves
change or motion of some sort.
- A conductor which moves perpendicular to a magnetic field
will set up an electric potential difference between its ends,
of size
V = v * L * B * sin(theta)
where v is the velocity of the conductor, L is its length,
B is the strength of the magnetic field, and theta
is the angle between the velocity of the conductor and the direction
of the magnetic field.
- If an induced voltage is applied to an electric circuit, it can
cause an induced current to flow through the circuit.
- Any work done by an induced current is taken from the kinetic
energy of the moving conductor; one must apply a constant force
to the conductor to keep it moving at a constant speed.
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Copyright © Michael Richmond.
This work is licensed under a Creative Commons License.