P2

Question 1

What is the equation for GPE?

Answer 1

m x g x h

Question 2

What is the equation for KE?

Answer 2

1/2 x m x (v)2

Question 3

A 3000 kg helicopter

hovering at 20 m, what is its GPE?

Answer 3

3000 x 10 x 20 = 600,000J

Question 4

What is bio-energy?

Answer 4

The power we produce from Biomass such as plants and animal matter.

Question 5

Name 2 advantages and 2 disadvantages of Bio-energy

Answer 5

Advantages:
■ The fuel is cheap.
■ It helps get rid of waste, which can cause smells and pollution.
■ It is not using up limited resources like coal: biomass cannot run
out.
Disadvantages:
■ Burning the fuel creates carbon dioxide, a greenhouse gas.
However, if you grow crops that absorb the same amount of
carbon dioxide from the air that is created by burning them, the
effect on the environment is less harmful.
■ Collecting waste in big enough amounts to generate energy can
be difficult.
■ If trees aren’t grown especially for fuel, and re-planted, the result
is deforestation.

Question 6

what is geothermal energy?

Answer 6

It is the energy extracted from the natural heat

that exists deep within the Earth.

Question 7

Name to advantages and 2 disadvantages of geothermal energy

Answer 7

Advantages:
■ Geothermal energy doesn’t produce any pollution.
■ Running costs for a geothermal power station are very low.
Disadvantages
:■ It is difficult to find suitable sites for geothermal power stations.
The hot rocks have to be of a suitable type and depth, and the
rocks above them have to be soft enough to drill through. There
are hardly any sites in the UK.
■ If not carefully managed, a borehole can ‘run out of steam’ and
may not be useable again for several decades.
■ Occasionally, dangerous gases and minerals can come out of a
borehole, and it may be difficult to dispose of them.

Question 8

what is hydroelectricity?

Answer 8

The extraction of energy from the energy in flowing water

Question 9

Name to advantages and 2 disadvantages of hydroelectricity

Answer 9

Advantages:
■ No waste or pollution is produced.
■ Once construction is completed, operating costs are
very low.
■ Electricity can be generated constantly because water
can be stored and used as needed.
Disadvantages:
■ Dams are very expensive to build.
■ Hydroelectricity sites are often remote, which leads to
higher distribution costs.
■ Suitable sites for large-scale projects are hard to find.

Question 10

what is solar energy?

Answer 10

Solar energy is energy

from the sun.

Question 11

What is Passive solar design?

Answer 11

The design involves designing buildings to

make the most of the sun’s natural heat.

Question 12

What is Active solar heating?

Answer 12

Water is pumped through pipes into solar panels (called

collectors) on the roof, and heated by the sun.

Question 13

What is Photovoltaic cells?

Answer 13

They contain silicon, which

convert energy from the sun into electricity.

Question 14

Name to advantages and 2 disadvantages of solar energy

Answer 14

Advantages:
■ Once the solar power plant is constructed, running
costs are very low.
■ Solar energy can be used to generate electricity in
remote places.
■ No waste or pollution is produced.
■ Energy is usually generated at or near where it will
be used, keeping transmission and distribution
costs to a minimum.
Disadvantages:
■ It doesn’t work at night.
■ Photovoltaic (PV) cells are very expensive (but they
are getting cheaper).

Question 15

What is wind energy?

Answer 15

The energy extracted from the movement of warmer air rising and cooler air moving in to replace it. This movement of air is the wind.

Question 16

Name to advantages and 2 disadvantages of wind energy

Answer 16

Advantages:
■ Once the wind turbine is built, running
costs are very low.
■ No waste or pollution is produced.
■ The land occupied by a wind farm can
still be used for farming.
■ Wind farms can become tourist
attractions.
Disadvantages:
■ No wind, no power.
■ Some people object because they feel
wind farms spoil the view.
■ Wind farms create a constant low-level
noise.
■ They can interfere with television
reception and radar.

Question 17

what is wave energy?

Answer 17

Energy extracted from the movement of the waves in the sea.

Question 18

Name to advantages and 2 disadvantages of wave energy

Answer 18

Advantages:
■ Once constructed, running costs are very low.
■ No waste or pollution is produced.
■ Wave-energy generators are capable of producing
large amounts of energy.
Disadvantages:
■ Wave-energy generators are only effective where
they are exposed to strong waves.
■ They can be noisy.
■ Wave-energy generators may be a hazard to ships
and leisure craft.

Question 19

what is tidal energy?

Answer 19

The energy extracted from the rising and falling of the sea

Question 20

Name to advantages and 2 disadvantages of tidal energy

Answer 20

Advantages
■ Running costs are very low.
■ No waste or pollution is produced.
■ The technology is very reliable.
■ No fuel is required.
■ The amount of electricity and the time when it is produced is
totally predictable.
Disadvantages
■ There are only a few suitable places for tidal energy projects.
■ Tidal stream technology is at a very early stage of development.
■ Tidal schemes are expensive to install compared with other
renewable energies.
■ Damming bays or inlets can affect the environment over a large
area.
■ Barrage schemes will only provide energy for about 10 hours each
day, as the tide moves in and out.

Question 21

What is the equation for efficiency?

Answer 21

Efficiency (%) = Useful Energy Out
—————————– x 100
Total Energy In

Question 22

Calculate the efficiency of a runner who produces of 500J of kinetic energy from 2500J of chemical
energy.

Answer 22

20%