Energy topic Complete Revision Flashcards
Energy Definition
Ability/power to do physical work
Measurement units for energy
Joules (J) or Watts (W)
Energy types
Thermal (heat), Light, Sound, Chemical, Kinetic, Nuclear, Gravitational Potential (GPE), Electrical, Elastic
Thermal Energy is…
An energy type conserved in living or non-living organisms with a temperature above -273˚C (absolute zero)
Gravitational Potential Energy is…
A type of energy found in anything that has the power to defy gravity in it’s movement or in it’s moving direction for a finite (limited) period of time (e.g. rock climbers and planes)
Law of Energy Conservation
[Energy] Can be transferred from one to another form, but not produced or destroyed
In living organisms, energy is vital for…
All physical activity (riding bikes, weight lifting, etc.)
Energy used by living animals as “fuel” for everyday tasks
Chemical energy (stored in food). When used, the stored energy changes into kinetic energy to carry out required activity.
Chemical energy in food is measurable. True or False?
True
Energy transfer methods
Conduction, Convection, Radiation.
How does radiation work and where does it transfer energy the best? What surface colour absorbs radiated heat the best?
Logistics of radiation = transferring heat energy via infrared electromagnetic waves. Requiring no particles for this process, radiation works best in a vacuum like space which contain no particles of any sort to interfere with the wave transmission. Black is a good surface for absorbing AND emitting radiated heat.
Thermometers can measure the amount of heat energy in solid objects. True or False?
False. Thermometers can measure the overall temperature of an object due to internal heat energy, but do not have the ability to calculate the exact amount of energy in joules or watts in a solid object.
What are the two categories of energy source?
Non-renewable and renewable
Names of 3 non-renewable sources of electrical energy
3 chosen out of coal, oil, gas (fossil fuels), and nuclear metal energy
Names of 4 renewable sources of electrical energy
4 chosen out of solar, wind, geothermal, biomass, tidal, and hydroelectric
Disadvantages of wind as a renewable source of energy
- If there is no wind, there is no energy produced
- windmill blades chopping in the wind are noisy and spoil countryside (usual installation area) views
Advantages of hydroelectricity dams as a renewable source of energy
- No fuel costs necessary
- Unless a severe drought occurs, the water supply will never run out
Advantages and disadvantages of fossil fuels as an energy source
Advantages
- Electricity generated is cheap and affordable
- Stations can be built anywhere
Disadvantages
- Burning fuels releases pollutant gases into the atmosphere
- Fossil fuel stations require lots of fuel to work efficiently
Changing of liquid to solid
Freezing
Evaporation is…
The changing of a liquid into a gas due to higher or lower temperatures than it can withstand as a liquid.
Bad energy conductors are called…
Insulators
Purpose of insulators
To prevent the accidental (and potentially harmful) discharge of electricity from metal-made appliances, wires, tools, and objects by absorbing the charge into the insulating material, usually a top layer over such metal products.
