P1 - Energy

Question 1

Energy stores Examples

Answer 1

• Thermal
• Kinetic
• Gravitational potential
• Elastic potential
• Chemical energy
• Magnetic
• Electrostatic
• Nuclear

Question 2

Kinetic energy equation

Answer 2

E = 1/2mv^2

kinetic energy = 1/2 x mass x (speed)^2

Question 3

Gravitational potential equation

Answer 3

E = mgh
G.P.E = mass x gravitational field strength x height

Question 4

elastic potential equation

Answer 4

E = 1/2ke^2
E.P.E = 1/2 x Spring constant x extension

Question 5

Specific heat energy equation

Answer 5

change in E = mc(change in)temperature

change in E = mass x S.H.C x change in temperature

Question 6

power equation

Answer 6

P = w/t
power = work done/time

Question 7

conservation of energy principle

Answer 7

energy can be transferred usefully, stored or dissipated, but can never be created or destroyed.

Question 8

ways to reduce unwanted energy transfers

Answer 8

lubrication

thermal insulation

Question 9

Lubrication

Answer 9

Lubricants can be used to reduce the friction between the objects’ surfaces when they move.

Question 10

conduction

Answer 10

the particles vibrate more and collide with each other. During these collisions, energy is transferred between the particles’ kinetic energy stores

Question 11

convection

Answer 11

Materials with a higher thermal conductivity transfer energy between their particles at a faster rate. The particles are free to move the space between individual particles increases . This causes the density of the region being heated to decrease. Energetic particles move away from hotter to cooler regions.

Question 12

cavity walls

Answer 12

made up of inner and outer wall and have an air gap in the middle. The air gap reduces the amount of energy transferred by conduction in the walls.

Question 13

loft insulation

Answer 13

can reduce convection currents being created in lofts.

Question 14

double-glazed windows

Answer 14

they have an air gap between two sheets of glass to prevent energy transfer by conduction through windows

Question 15

drought excluders

Answer 15

around doors and windows to reduce energy transfers by convection

Question 16

efficiency equation

Answer 16

efficiency = useful output / total output

Question 17

non renewable resources examples

Answer 17

coil
oil
natural gas

Question 18

renewable resources examples

Answer 18

the sun
wind
water waves
hydro-electricity 
bio-fuel
tides
geothermal

Question 19

non-renewable resources

Answer 19

run out one day
damage the environment
provide most of our energy

Question 20

renewable resources

Answer 20

never run out
most of them do damage but not as bad as non-renewable
don’t provide much energy
some are unreliable as they depend on the weather.

Question 21

Transport energy resources

Answer 21

N
- petrol and diesel use fuel created from oil
- coal is used in some old-fashioned steam trains
R
- Vehicles that run on pure bio-fuels

Question 22

Heating energy resources

Answer 22

N
- Natural gas is used to heat up water
- coal for fire places
- Electric heaters which uses energy generated from NRR
R
- A geothermal heat pump
- Solar water heaters work by using the sun to heat up water 
- Burning bio-fuel

Question 23

wind power

Answer 23

• no pollution
• spoil the view
• very noisy
• initial costs are high but no fuel or minimal running costs
• no permanent damage to the landscape

Question 24

Solar cells

Answer 24

• remote places
• no pollution
• only in daytime
• initial costs are high
• energy is free and running costs are almost nil.
• generate electricity on a relatively small scale

Question 25

Geothermal power

Answer 25

- where hot rocks are quite near the surface. Slow decay of various radioactive elements deep inside the earth - free energy - reliable - little damage to the environment - generate electricity or heat buildings directly

Question 26

hydro-electric power

Answer 26

- requires the flooding of a valley by building a big dam - no pollution - big impact on the environment - flooding of valley and possible loss of habitat - unsightly when dried up - provide an immediate response

Question 27

wave power

Answer 27

- lots of small turbines around the coast - no pollution - disturbs the seabed and the habitats of marine animals - hazard to boats - spoil the view - large scale

Question 28

Tidal Barrages

Answer 28

- big dams with turbines build into them - gravitational pull of the sun and moon - no pollution - preventing free access by boats - altering habitat - spoils the view - happen twice a day with no fail - lower tides will provide less energy than bigger tides

Question 29

Bio-fuels

Answer 29

- renewable energy source - created from plant products or animal waste - solid, liquid or gas and can be burnt to make electricty - fairly reliable as crops take a relatively short time to grow - cannot respond to immediate energy demands - stored for when they are needed - cost is very high - some regions have large forests cleared and use them for bio-fuels. This means a lot of animals are losing their habitats - Burns vegetation and it increases CO2 and methane emmisons

Question 30

ways in which non-renewables are reliable

Answer 30

- enough fossil and nuclear fuels to meet current demands - extracted from the earth at a fast enough rate that power plants always have fuel in stock - respond quickly to changes in demand - running and fuel extraction costs are fairly low

Question 31

Non-renewables creating environmental problems

Answer 31

- coal, oil and gas release CO2 - coal and oil releases sulfur dioxide - coal mining can spoil the view - oil spillages - nuclear waste - nuclear power

Question 32

Why we still depend on fossil fuels

Answer 32

- electricity - oil is used to fuel cars - gas is used to heat homes and cook food

Question 33

Why people want more renewable energy resources

Answer 33

- very damaging to the environment - non-renewables will run out - pressure from other countries - car companies have been affected by this change in attitude

Question 34

Renewables are limited

Answer 34

- building power plants costs money - arguments of where to put them - some energy resources are unreliable - personal changes can be quite expensive