Energy Flashcards
Conservation of Energy
Energy cannot be created nor destroyed only re-arranged or dissipated
Define Dissipation
To spread out
How to reduce the amount of heat loss in a water tank
Insulation
Have a lid
Create an area of vacuum around the tank
How to reduce the amount of heat loss in moving mechanical parts
Reduce friction within the mechanism
Where is heat lost in a house
Roof, Walls, Windows, Floor
How do you prevent the loss of heat in a house
Double/Triple Glazing. Wall Insulation. Carpets. Draught excluders. Loft Insulation. Cavity Wall Insulation
What links Efficiency, Energy Used and Total output
Efficiency = Used Energy / Total Energy Input
What are the main fuels
Oil, Coal, Gas,
What links Kinetic Energy, Mass and Speed
Kinetic Energy (J) = 0.5 x mass (kg) x speed^2 (m/s)
What links Thermal Energy, Mass, SHC, Change in heat
Thermal Energy = mass (kg) x specific heat capacity (J/kgoC) x change in temperature
What links Elastic Potential Energy, spring constant and extension
Elastic Potential Energy (J) = 0.5 x Spring Constant (N/m) x extension^2 (m)
What links GPE, Mass, GFS, Height
GPE (J) = Mass (kg) x GFS (N/kg) (9.8) x Height
Renewable energy sources
Geothermal, Nuclear, Biofuel, Wind, Hydroelectricity, Tidal, Waves, Solar
What equation links; Energy transferred, Power and Time
Power (W) = Energy Transferred (J) / Time (s)
What equation links; Work done, Power and Time
Power (W) = Work Done (J) / Time (s)
What equation links; Useful energy output transfer, Efficiency and Total input energy transfer
Efficiency = Useful energy output transfer / Total input energy transfer
How does a wind turbine work?
Wind
Blades spin a generator
Generator creates thermal energy
Electricity
What are the energy stores?
Kinetic, Gravitational, Thermal, Chemical, Atomic, Magnetic, Electrostatic, Elastic Potential
If energy is transferred into an objects kinetic energy store, what happens to the speed?
Increases
What is Specific Heat Capacity?
The amount of energy it takes to raise the temperature of 1KG of an object by 1C
What is an energy pathway?
A means or process by which energy is transferred from one store to another (Stretching a rubber band (Chemical –> Elastic))
What are the energy pathways
Mechanical (Moving something)
Electrical (Electrons in a circuit)
Heating by particles (Vibrations of particles)
Heating by radiation (Transferred by waves)
