What is energy?
The ability to do work or cause change.
Name 3 types of kinetic energy.
.Light, Heat, Sound (also: Electrical, Wind).
Name 3 types of potential energy.
Chemical (food, fuel, batteries), Elastic, Gravitational.
Kinetic Energy
Energy of movement (e.g., moving car, rolling ball).
Potential Energy
Stored energy ready to be used (e.g., battery, stretched spring).
Law of Conservation of Energy
Energy cannot be created or destroyed, only changed from one form to another.
What is an energy transformation?
Energy changing type (e.g., electrical → light in a bulb).
Energy transfer is
Energy moving from one place/object to another (e.g., heat from stove to pot).
hat does a Sankey diagram show?
How energy is transformed and how much is useful vs wasted.
Conduction
Heat transfer through Soilds (Spoon in hot drink)
Convection
Heat transfer in liquids and gases (hot air rises, cool air sinks)
Radiation
Heat transfer as waves ( SUN ) occurs in space
3 things you need for electric circuit
Battery, wires, globe (lamp)
When circuit is closed what happens
Electricity flows
Energy Efficiency
Useful energy divided by total energy x100%
Why are most energy conversions inefficient
Energy is lost as heat or sound
2 technologies that improve efficiency
LED lights, Hybrid Cars (Tesla)
Why is energy efficiency important
Saves money, reduces resource use, lowers pollution and green house gases
