A.C. Generator

The factors listed above show that:

A voltage and current are generated when a conductor such as a wire cures through the magnetic field lines The faster the lines are cut the larger the induced voltage and current

Step 3

As a result, the current induced in the coil flows first in one direction and then in the opposite direction

Step 1

As the coil orates, its wire cut through magnetic field lines and a current is induced in them

We can also generate a voltage and current by pushing a magnet into a coil. The size of the induced voltage (and current) can be increased by:

Moving the magnet more quickly Using a stronger magnet Using a coil with more turns Using a coil with a larger cross-sectional area

The size of the induced volute (and current) can be increased by:

Moving the wire more quickly Using a stronger magnet Wrapping the wire into a coil so that more pieces of wire move through the magnetic field line

How is the coil rotated?

The coil is rotated by an external force (e.g. the motion of a wind turbine or steam turbine)

What does the direction of the induced current depend upon?

The direction of the motion. If the direction of movement is reversed, so too is the direction of the induced current

What is the frequency of an alternating current?

The number of complete cycles it makes each second. If an alternator coil rotates twice in a second, the frequency of the alternating current produced 2 Hz

What is Faraday's Law of Electromagnetic induction?

The size of the induced voltage across the ends of a wire (coil) is directly proportional to the rate at which the magnetic lines of flux are being cut

Step 2

The wire moves through the field d then down for each turn of the coil

What happens if we hold the wire or magnet stationary?

There is no cutting of field lines so no voltage or current is generated. If we move the wire horizontally between the poles of the magnet, again there are no lines being cur and therefore no voltage or current is generated

Step 4

This kind of current is called alternating current. A generator that produced alternating current is called an alternator

When is a voltage induced?

When we move a wire across a magnetic field at right angles, a voltage is indeuc or generated in the wire. If the wire is part of a complete circuit, a current flows. This is called electromagnetic induction