Energy Flashcards
What equation do you use for calculating kinetic energy?
………………………..2
Ek = 0.5 x m x v
What is GPE?
It is the ENERGY STORED in an object due to its position ABOVE the EARTH’S SURFACE.
What equation do you use for calculating gravitational potential energy?
Ep = m x g x h
What is meant by the specific heat capacity of a substance?
It is the amount of ENERGY required to raise the TEMPERATURE of 1 kg of the SUBSTANCE by 1 °C.
What equation do you use for calculating specific heat capacity?
change in thermal energy = mass x specific heat capacity x temperature change ΔE = m x c x ∆θ
What is meant by the conservation of energy?
Energy can be transferred usefully, stored or dissipated but it CANNOT be created or destroyed
What is meant by a closed system?
Where no ENERGY can ENTER or LEAVE.
What is work?
Work done is whenever energy is transferred from ONE STORE TO ANOTHER.
What equation do you use for calculating work done?
work done (J) = force (N) x distance
What is power?
It is the RATE at which ENERGY is TRANSFERRED or the rate at which WORK IS DONE.
What equation links to power energy transferred and time?
power (W) = energy transferred (J) / time (s)
What equation links to power work done and time?
power (W) = work done (J) / time (s)
What two equations do you use to calculate efficiency?
Efficiency = Useful output energy transfer / Total input energy transfer
Efficiency = Useful power output / Total power input
What is meant by thermal conductivity?
The RATE at which HEAT passes through a specified material.
Name the 3 main fossil fuels
- Coal
- Oil
- Gas
Give 3 advantages of using fossil fuels for energy.
- RELIABLE.
- They release a great deal of ENERGY
- They are ABUNDANT (existing or available in large quantities) and relatively CHEAP.
Give 3 disadvantages of using fossil fuels for energy.
- Releases huge amount of CO2
- They are NON-RENEWABLE
- They can release OTHER POLLUTANTS.
What is nuclear power and what 2 main elements do nuclear power plants use?
Nuclear power is electric or motive power generated by a nuclear reactor. Its NON-RENEWABLE, and nuclear power plants run on elements URANIUM and PLUTONIUM.
Give 2 advantages of using nuclear power.
- Does not release CO2
- Extremely RELIABLE
Give 2 disadvantages of using nuclear power.
- Nuclear power plants contain highly DANGEROUS RADIOACTIVE MATERIALS.
- DECOMMISSIONING a nuclear power plant takes many YEARS and is extremely EXPENSIVE.
What 2 major benifits are there from switching from coal to gas?
- Burning gas generates LESS CO2 than burning coal (contributes LESS to CLIMATE CHANGE.
- Gas-fired power stations are FLEXIBLE. They can be switched on QUICKLY during periods of high demand (SHORT start up time compared to coal).
What is meant by a renewable energy resource?
It is one that is being REPLENISHED as it is USED.
Name 3 non-renewable energy resources.
Any 3 from:
- coal
- oil
- gas
- nuclear
Name 3 renewable energy resources.
Any 3 from:
- wind power
- solar power
- hydroelectric power
- geothermal
- waves
- tides
- wood
Give a disadvantage of renewable energy resources.
They all generate ELECTRICITY so for TRANSPORT would not be so great as almost all cars in the UK run on PETROL and DIESEL (FOSSIL FUELS).
Give 2 advantages of renewable energy resources.
- They will NEVER run out
- They do NOT add any CO2 to the atmosphere, so do not contribute to climate change.
Why is it better to use more renewable energy resources rather than non-renwable resources?
- Non-renewables cause pollution
- Renewables are replaced
- Using more renwables conserves non-renwables
What is hydroelectric power?
When river water is trapped behind a dam and used to turn turbines .
What is geothermal energy?
When hot water and steam from deep underground can be used to drive turbines.
What are fuels?
Sources of energy.
Name 2 biofuels.
Any 2 from:
- Ethanol fuel
- Biodiesel
- Diesel fuel
- Biogas
