Energy Flashcards
What acronym helps remember all energy stores? - Energy
GELTNECKS
What are the 4 ways of transferring energy? - Energy
Mechanical work (force moving an object)
Electrical work (charges moving due to voltage)
Heating (due to temperature difference)
Radiation (energy transferred as a wave)
What diagrams show energy transfers? (2) - Energy
Transfer diagrams (with an explanation) Sankey Diagrams (in proportion, showing how much energy is transferred to what)
Describe what happens when energy is wasted + name an example of how energy is lost - Energy
Energy is dissipated into the surroundings when wasted
Friction between surfaces reduces loss of energy through heat
What is the equation for kinetic energy?
Kinetic energy (J) = 1/2 x mass (kg) x velocity^2 (m/s)
What is the equation for elastic potential energy?
Elastic potential energy (J) = 1/2 x spring constant (N/m) x extension^2 (m)
What is the equation to calculate gravitational potential energy?
GPE (J) = mass (kg) x gravitational field strength (N/kg) x height (m)
What is the equation to calculate work done?
Work done (J) = force (N) x distance (m)
What is the equation for power?
Power (W) = Energy (J) / Time (S)
What is the equation for efficiency?
Efficiency = useful energy transferred / total energy supplied
Name 1 way to reduce energy loss - Energy
By using a lubricant to reduce friction, meaning less energy is lost as heat
What is thermal conductivity? - Energy
A measure of how well a material conducts energy when it is heated
Why are metals good conductors of heat? - Energy
When metals come into contact with heat, the ions, which are very close together, vibrate against each other, causing transfer of energy through these vibrations
What should be used to keep houses and buildings warm? - Energy
Substances that do not have high conductivity, and therefore maintain heat within the building
What is the equation for specific heat capacity? - Energy
Change in thermal energy = mass x SHC x temperature change
