energy basics
What is the definition of energy?
Energy is the ability to do work or cause change.
Draw an energy transfer diagram for a torch turning on.
Chemical → Electrical → Light (+ Heat)
define conduction
Heat transfer through direct contact between particles
define potential energy
Stored energy due to an object's position or condition.
define kinetic energy
energy of motion
What does it mean when energy is transferred?
Energy is passed from one object or place to another
Draw an energy transfer diagram for a toaster heating bread.
Electrical → Heat → (Sound/Light energy losses)
define convection
Heat transfer through the movement of fluids (liquids or gases).
name 3 types of potential energy
Gravitational, Chemical, Elastic or nuclear
name 3 types of kinetic energy
heat/thermal, sound, electrical, mechanical
State the law of conservation of energy
Energy cannot be created or destroyed; it can only be transferred or transformed
Identify the energy transformation in a wind turbine.
Kinetic (wind) → Electrical
define radiation
Heat transfer through electromagnetic waves; no particles needed
Give three examples of gravitational potential energy.
A book on a shelf, water in a dam, a person at the top of a hill.
What happens to kinetic energy when an object speeds up?
increases
Convert 4 kJ to joules.
4000 Joules
What is meant by energy transformation?
Energy changing from one form to another
give an example of conduction
hot bowl heating hands
Three examples of chemical potential energy.
Food, petrol, batteries.
Give an example of kinetic energy at school.
A ball being thrown, a student running, a fan spinning.
2500 J into kJ
2.5 kJ
Example where both potential and kinetic energy are involved.
A roller coaster: Potential at the top → Kinetic as it moves down
example of convection
warm air rising and cool air sinking in a room
Compare gravitational and elastic potential energy.
Gravitational depends on height; elastic depends on stretching or compression
If you drop two balls of different masses- one heavy and one light- from the same height, which has more kinetic energy at the bottom?
The heavier ball (more mass → more KE).