Topic 1- Energy Flashcards
key definitions + concepts
Closed System
system that experiences NO NET CHANGE in its TOTAL ENERGY when ENERGY TRANSFERS OCCUR within it
Conservation of Energy
The law that energy can be:
- transferred
- stored
- dissipated
BUT never
- created
-destroyed
Efficiency
USEFUL ENERGY OUTPUT over TOTAL ENERGY INPUT
Elastic Potential Energy
-store of energy for stretched/compressed objects
- DIRECTLY PROPORTIONAL TO MASS OF OBJECT
- DIRECTLY PROPORTIONAL TO EXTENSION squared /COMPRESSION squared
Fossil Fuel Examples
coal, oil + gas
Gravitational Pot. Energy
- store of energy in all raised objects
- DIRECTLY PROPORTIONAL TO:
-MASS
-DISTANCE RISEN
-GRAVITATIONAL FIELD STRENGTH AT THAT POINT
Joule
unit for energy
Kinetic Energy
-store of energy in all moving objects
-DIRECTLY PROPORTIONAL TO
-MASS
-VELOCITY SQUARED
Power
RATE of ENERGY TRANSFER/RATE OF WHICH WORK IS DONE
Renewable Energy Resource
resource that can be REPLENISHED whilst its being USED ( it is INFINITE )
Specific Heat Capacity
amount of energy req. to raise the temp of 1KG of a substance by 1 degree
System
single/group of OBJECTS
Thermal Conductivity
measure of how well a material conducts energy when it is heated
Waste Energy
energy that is not usefully used for purpose of system
Watt
unit of power
Work Done
energy transfer when FORCE acts over a DISTANCE
