Physics

Energy

Energy is one of the most useful ideas in physics because it gives you a way to follow what happens in a system from start to finish. Whether an object speeds up, a spring stretches, or heat moves from one place to another, the total energy budget tells the story. This topic hub focuses on conservation of energy, work and power, and the thermal side of energy in real-world systems.

Learning Path

1 Study

Conservation of Energy

Build a clear picture of how kinetic, potential, and thermal energy transform without being created or destroyed.

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2 Explore

Energy Conservation Explorer

Adjust a system and watch energy move between forms as conditions change.

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3 Experiment

Energy Skate Park Lab

Test how height, speed, friction, and track shape affect energy transformations in motion.

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4 Reference

Core energy ideas to remember

Keep these definitions handy as you solve problems and interpret graphs.

  • Energy is the capacity to do work, and it appears in forms such as kinetic, potential, thermal, chemical, and electrical energy.
  • In a closed system, total energy is conserved even when it changes form or is transferred between objects.
  • Work and heat are key pathways for energy transfer, especially in motion and thermodynamics problems.

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Common Questions

What is the difference between energy and work?

Energy is the ability to do work, while work is one way energy is transferred when a force causes displacement.

Why does energy sometimes seem to be lost?

Energy is not destroyed; it often changes into thermal energy, sound, or other less visible forms because of friction and other interactions.