P1 Energy Flashcards
What are the 8 different types of energy stores?
- Thermal
- Kinetic
- Gravitational
- Elastic
- Chemical
- Magnetic
- Electrostatic
- Nuclear
What are the different ways energy can be transferred? (Pathways)
- Mechanically
- Electrically
- Heating
- Radiating
How is energy transferred by heating with a kettle and water?
- Energy is transferred to the water by heating into the water’s thermal energy store which causes the temperature to rise
- Energy is electrically transferred to the thermal energy store of the kettle’s heating element, which transfers energy by heating to the water’s thermal energy store
Work done
- Energy transferred
- Work can be done when current flows or by a force moving an object
Give examples of work done
- Initial force exerted by a person throwing a ball
- A ball falling
- Friction between the cars breaks
Movement
- Anything that moves has it’s own kinetic energy store
- If energy is transferred to, then the object speeds up and from the object slows down
What is the effect of mass and speed on the kinetic energy store of an object?
The greater the mass and the faster it is going means the more energy there will be in the Kinetic energy store
Kinetic energy formula
E(k) = 1/2 * mv ^ 2
GPE
- Lifting an object in a gravitational field requires work which causes a transfer of energy to the gravitational potential energy store of the raised object
What factors effect GPE?
- Mass
- Height
- Strength
GPE equation
E(p) = mgh
What transfer of energy happens with falling objects?
- Energy form the gravitational potential energy store is transferred to its kinetic energy store
- When there is no air resistance, the energy lost from g.p.e store is the same amount of energy gained in the kinetic energy store
Elastic potential energy
- Stretching or squashing an object can transfer energy to its elastic potential energy
- As long as the limit of proportionality has not been exceeded, energy in the eps store
EPE equation
E(0) = 1/2k * e ^ 2
Specific Heat Capacity
- Specific Heat Capacity is the amount of energy needed to raise the temperature of 1kg of substance by 1 degrees celcius
- More energy needs to be transferred to the thermal energy store to increase their temperature than others
Specific Heat Capacity equation
change in thermal energy (E) = mc * change in temperature (degrees celcius)
Law of conservation of energy
Energy cannot be created or destroyed, only transferred
What is ‘wasted energy’?
Dissipated energy is energy that is being stored in a way that is not useful
Power
Power is the rate of energy transfer, or the rate of doing work
What is power measure in?
Watts. (1 watt = 1 joule of energy transferred per second)
Power equations
Power = Energy transferred / time Power = Work done / time
What is a powerful machine?
A machine that transfers a lot of energy in a short space of time
What does lubrication do to frictional forces?
Reduces frictional forces
Give examples of frictional forces
Air resistance
What objects help remove frictional forces?
Lubricants
Conduction
- Particles vibrate and collide more with each other
- Energy is transferred between the particles’ kinetic energy stores
Thermal conductivity
A measure of how quickly energy is transferred through a material in this way
Convection
- Warmer and less region will rise above denser, cooler regions
- Energetic particles move away from hotter to cooler regions
What are some methods to reduce energy transfer by heating (Insulation)
- Thick walls made from a material with a low thermal conductivity
- Thermal insulation
- Loft insulation
- Double-glazed windows
- Draught excluders
- Cavity wall insulation
Efficiency equation
Useful output energy transfer / total input energy transfer
useful power output / total power input
Why is no device 100% efficient?
Energy is usually transferred to useless thermal energy stores
What are the 3 main non-renewable energy resources?
- Coal
- Oil
- Natural gas
Give some main renewable energy resources
- The sun
- Wind
- Water waves
- Hydro-electricity
- Bio-fuel
- Tides
- Geothermal
What are some uses of non-renewable resources?
- Heating
- Transport
Wind power
- Wind turbines in exposed places like moors and coasts
- No pollution
- Very noisy
- Initial cost is high
- No permanent damage
Solar power
- No pollution
- Remote places
- Very reliable source in the daytime
- Can’t increase the power output
- Initial costs are high
Geothermal power
- Use the slow decay of various radioactive elements deep inside the earth
- Does minor damage to the environment
- Aren’t many suitable locations
Hydro-electric power
- No pollution
- Flood allows kinetic energy
- Immediate response
- Cause rotting to the environment
- Initial costs are high but no fuel costs
Wave power
- No pollution
- Fairly unreliable
- Initial costs are high but it is never likely to provide energy on a large scale
Tidal barrages
- Big damns built across river estuaries
- No pollution
- Tides produces by the gravitational pull of the sun and moon
- Initial costs are moderately high, but no fuel costs and minimal running costs
Bio fuels
Renewable energy resources created from either plant products or animal drug
Are bio fuels carbon neutral?
- Arguably if you grow plants at the rate you are growing things
Are biofuels reliable?
- Semi reliable
- They cannot respond to immediate energy demands
- The cost is very high
are non-renewables reliable?
- Yes
- They can respond to immediate energy demands very quickly
What are some environmental problems of non-renewable resources?
- CO2 is released and contributes to global warming
- Sulfur dioxide can cause acid rain
- Coal mining messes the landscape
- Oil spillages cause serious environmental problems
- Nuclear waste is very dangerous and difficult to dispose of
What are some environmental problems of non-renewable resources?
- CO2 is released and contributes to global warming
- Sulfur dioxide can cause acid rain
- Coal mining messes the landscape
- Oil spillages cause serious environmental problems
- Nuclear waste is very dangerous and difficult to dispose of
