Insert the following words into the text below. You will find these words in the wordsearch above.

BIOMASS

CIRCUIT

COAL

CLOSER

ELECTRICITY

ELECTROMAGNETIC

FASTER

FLUX

GALVANOMETER

GENERATOR

INDUCED

INDUCTION

LINES

MAGNET

NUMBER

POLE

REDUCE

REVERSED

RIGHT

TIDAL

SIZE

SPEED

STRAIGHT

STATIONARY

STATIONS

STRENGTH

STRONGER

TRANSFORMERS

TURNS

VOLTMETER

WIRE

This is a very important physics discovery. Our modern lifestyle would not be possible without electric power generation.... and -------------- --------- is the process by which wind, wave, -----, HEP, ---, gas, ----, nuclear and ------- energy is changed into -----------.

If a ------ is moved into a coil of wire that is part of a complete ------- a voltage is ------- across the ends of the ---- a current is produced (induced) in the wire. If the magnet is then moved out of the coil, or the other ---- of the magnet is moved into the coil, the direction of the induced voltage (current) is --------.

The ---- of the induced voltage depends upon the 'rate of cutting of magnetic ---- lines'

So:

If the magnet is ---------- with respect to the magnetic field no voltage is induced and therefore no ------- flows. If the wire 'cuts through' the lines of magnetic flux (crosses through field lines) a current is registered on a sensitive ------------ (either a --------- or ammeter)

The ------ the magnet 'cuts the magnetic flux lines' the bigger the voltage and the bigger the current flow. As if you move the magnet faster you cut through more ----- of magnetic flux in a given time and you therefore get a bigger induced current and voltage.

The more ----- of the wire that 'cut the magnetic flux lines' (possible if you wind the wire into a coil!) the bigger the voltage and current induced.

If you use a -------- magnet the magnetic flux lines are ------ together - therefore as you move the magnet it ---- through more lines in a given time and you get a bigger induced current and voltage.

------------ work by electromagnetic induction. They are used to change the voltage of an a.c. supply. At power --------, transformers are used to produce very high voltages before the electricity is transmitted to where it is needed through power lines (National Grid). Local transformers ------ the voltage to safer levels before the electricity is supplied to consumers.

An Electricity --------- works using electromagnetic induction.

If a wire, or coil of wire‚ cuts through a magnetic field, or vice-versa, a voltage (potential difference) is produced between the ends of the wire. This induced voltage causes a current to flow if the wire is part of a complete circuit.

The size of the induced voltage increases when:

• the ----- of the movement increases;

• the ------- of the magnetic field is increased;

• the ------ of turns on the coil is increased;

A changing magnetic field will also produce an induced voltage in a coil as this produces a changing magnetic flux pattern that even a stationary wire will experience.

The direction of the induced current is reversed if either the direction of the movement or the direction of the magnetic field is reversed. It can be found using Fleming's ----- Hand Dynamo Rule. The right hand rule predicts the direction of an induced current and RIGHT has an I in it - the symbol for current!)

ANSWERS