Slides in this set

Slide 1

Preview of page 1

e vi si o n
ysi c s R
l i e G r i ffin
By Cha…read more

Slide 2

Preview of page 2

Wind and Water Power
· Wind power - wind turbine is an electrical generator at the top
of a narrow tower. Power increases as wind speed increases
· Wave power - wave generator uses wave motion to drive the
turbine and a cable between the generator and the shore
sends electricity to the grid system
· Hydroelectric power - water collected in a reservoir flows
downhill and drives turbines at the foot of the hill
· Tidal power - tidal power stations trap the water behind a
barrange and then is released through turbines into the sea…read more

Slide 3

Preview of page 3

Fuel for Electricity
· Coal or oil-fired power stations (fossil fuel) - produce
steam that drives a turbine to produce electricity
(greenhouse gases produced)
· Gas-fired power station - natural gas (fossil fuel) is
burned in a gas turbine. This produces hot gases and air
that drives the turbine (greenhouse gases produced)
· Nuclear power station - uranium fuel releases thermal
energy via nuclear fission (the splitting of the nucleus).
Thermal energy is pumped through the core and turns
water into steam which drives the turbine (no
greenhouse gases produced)…read more

Slide 4

Preview of page 4

The Generation of electricity
using fossil fuels
· Coal/Fuel is burnt
· Water is heated to form steam
· The steam turns the turbine
· The turbine drives the generator,
which makes electricity…read more

Slide 5

Preview of page 5

The Government needs to
think of alternate ways of
making electricity because...
·1. We are using up our
fossil fuels
·2. Fossil Fuels cause
greenhouse gases.…read more

Slide 6

Preview of page 6

Dynamo Effect
Generators use something called the 'dynamo effect' to make electricity.
· An electric current is produced when a magnet is moved into a coil of wire in a circuit. The
direction of the current is reversed when the magnet is moved out of the coil. It can also be
reversed if the other pole of the magnet is moved into the coil.
Notice that no current is induced when the magnet is still, even if it is inside the coil. When you
turn the magnet constantly (e.g. anti-clockwise) the voltage will reverse every half-turn, making
an AC current.
· FOUR FACTORS affect the SIZE od the induced VOLTAGE
1) the STRENGTH of the MAGNET 2) the AREA of the COIL
the NUMBER OF TURNS on the COIL 4) the SPEED of the movement
· how GENERATORS work - they generate current by electromagnet induction (see above). all
generators need something to do the turning, this could be anything from a steam-driven turbine
to a waterwheel! a dynamo is a special type of generator, often used in bike lights, here the
magnet is rotated - not the coil. dynamo is attached to the wheel, as you turn the wheels, you
turn the magnet inside the dynamo.…read more

Slide 7

Preview of page 7
Preview of page 7

Slide 8

Preview of page 8
Preview of page 8

Slide 9

Preview of page 9
Preview of page 9

Slide 10

Preview of page 10
Preview of page 10


No comments have yet been made

Similar Physics resources:

See all Physics resources »