Energy Stores Flashcards
What are the 8 energy stores?
Kinetic, thermal, chemical, graviational potential, elastic potential, electrostatic, magnetic and nuclear
What is the equation for KE
KE = 0.5 X MASS X VELOCITY SQUARED
what is the equation for GPE?
GPE = MASS X GRAVITATIONAL FIELD STRENGTH X CHANGE IN HEIGHT
What is a closed system?
A collection of objects where there is no net change in the total energy
What are the 4 ways energy is transferred?
Mechanically, electrically, by heating and by radiation
What are useful devices?
Devices that transfer energy from one store to a useful store
How do you calculate efficiency?
Useful energy transferred / total energy supplied
How can you reduce energy waste?
Lubrication or thermal insulation
How does a moving object transfer energy?
Mechanically
What does insulation do?
It reduces the rate of energy transfer by heating
What is thermal conductivity?
How well an object transfers energy by conduction
What are cavity walls?
An inner and outer wall with an air gap in the middle
Why do cavity walls reduce heat loss?
Air has a low thermal conductivity
