Energy Cannot Be Created or Destroyed

The Law of Conservation of Energy says that energy can't be made from nothing or disappear—it just changes form.

How Energy Changes

When you eat food, your body turns the chemical energy into motion (kinetic energy) or heat (thermal energy). When you turn on a fan, electrical energy becomes kinetic (spinning blades) and sound.

Keeping Track of Energy

Scientists can track energy as it changes forms, but the total amount stays the same.

Real-World Connections

• A roller coaster car at the top has potential energy, which turns into kinetic energy as it goes down.
• When you burn wood, chemical energy becomes heat and light.