Energy Concepts
15 concepts · Grades 6-8, 9-12 · 17 prerequisite connections
Energy ties together motion, forces, and heat into one unifying framework. The central insight is conservation: energy is never created or destroyed, only transformed. A roller coaster converts potential energy at the top into kinetic energy at the bottom; a bouncing ball loses mechanical energy to thermal energy with each bounce. This family spans kinetic and potential energy, work and power, and connects forward into thermodynamics and fields.
This family view narrows the full physics map to one connected cluster. Read it from left to right: earlier nodes support later ones, and dense middle sections usually mark the concepts that hold the largest share of future work together.
Use the graph to plan review, then use the full concept list below to open precise pages for definitions, examples, formulas, and related guides.
Concept Dependency Graph
Concepts flow left to right, from foundational to advanced. Hover to highlight connections. Click any concept to learn more.
Connected Families
Energy concepts have 17 connections to other families.
All Energy Concepts
Energy
The capacity to do work or cause change in a physical system, measured in joules (J).
Work
The transfer of energy that occurs when a force causes an object to move through a distance in the direction of the force, calculated as.
Kinetic Energy
The energy an object possesses by virtue of its motion, equal to one-half times its mass times the square of its velocity.
Potential Energy
Energy stored in a system due to the position or configuration of its parts, ready to be converted into kinetic or other forms of energy.
Gravitational Potential Energy
Energy stored in an object due to its height above a reference point in a gravitational field: $PE = mgh$.
Elastic Potential Energy
Energy stored in an elastic object that has been stretched or compressed from its natural length.
Conservation of Energy
A fundamental law of physics stating that the total energy of an isolated system remains constant over time — energy can be transferred between objects.
Work-Energy Theorem
The net work done on an object by all forces acting on it equals the change in its kinetic energy.
Power
The rate at which work is done or energy is transferred, measured in watts (joules per second).
Mechanical Energy
The total of kinetic energy and potential energy in a mechanical system at any given moment.
Efficiency
The ratio of useful output energy (or power) to total input energy, expressed as a percentage — always less than 100% due to energy losses.
Simple Harmonic Motion
Oscillatory motion where the restoring force is proportional to displacement from equilibrium, producing sinusoidal position over time.
Conduction
Heat transfer through direct physical contact between particles, where faster-moving (hotter) particles collide with and pass kinetic energy to slower-moving (cooler) neighbours.
Convection
Heat transfer through the bulk movement of a fluid (liquid or gas) that carries thermal energy from one place to another.
Radiation (Heat Transfer)
Heat transfer through electromagnetic waves that require no medium — the only form of heat transfer that works through a vacuum.