Conservation of Energy
Energy can change from one form to another but is never created or destroyed.
- Energy takes many forms — light, heat, sound, electrical, and mechanical.
- In a device, energy transforms: a lamp turns electrical energy into light and heat.
- Energy is conserved — the total amount stays the same, even as it changes form.
Because no transformation is perfect, some energy always turns into heat, which is why devices warm up as they run.