1.1 Kinetic energy from
moving air turns the blades
on a wind turbine to
1.2 Some gases in the Earth's atmosphere
trap heat from the Sun increasing global
warming.Scientists disagree about how
much effect humans have on the increase
in levels of these Greenhouse gases.
1.3 Passive solar heating
uses glass to help keep
1.4 Photocells do not need fuel or
cables,need little maintenance and
cause no pollution.
2 Electricity generation.
2.1 Power = Voltage x Current.
2.2 In power stations fuels release energy as heat.Water
is heated to produce steam.The steam drives
turbines.Turbines turn generators.Generators produce
electricity. Efficiency = Output \ Total energy input x
2.3 Energy = Power x Time.
2.3.1 Nuclear fuels are
produced can cause
remain radioactive for a
188.8.131.52 The main forms of ionising
radiation are alpha,beta and
gamma.Their uses depend on their
penetrative and ionisation
2.4 A dynamo produces
electricity when coils of
wire rotate inside a
magnetic field.The size of
the current depends on
the number of turns,the
strength of the field and
the speed of rotation.
2.5 Transformers change
the size of the
electricity around the
country at high
voltage and low
3 Our Solar System.
3.1 Planets,asteroids and
comets orbit the Sun in
our Solar System.
3.2 When two planets
collide,a new planet and
a moon may be formed.
3.3 Medium-sized stars,such as our
Sun,were formed from nebulae and
will eventually become red
giants,white dwarfs and finally black
4 The Universe.
4.1 Scientists believe that the
Universe started with a Big
4.2 The Universe is explored by
telescopes on Earth and in
space.Large distances mean that it
takes a long time for information to
be received and makes inter-galactic
4.3 The Universe consists of many
galaxies.Models of the Universe
have changed over time and
sometimes these changes take a
long time to be accepted.
4.4 Most asteroids are between Mars and
Jupiter but some pass closer to
Earth.They are constantly being
monitored.An asteroid strike could cause
climate change and species extinction.