Energy Wastage
Physics: Edexcel IGCSE, topic 4.2.1
Wasted Energy
When one store of energy is transferred to another, some energy is wasted. Wasted energy moves into unwanted stores of energy. The wasted energy dissipates (spreads out) to anything nearby.

Car engines - noise and heat
- Car engines make a lot of noise and get hot.
- The useful energy store is the kinetic store.
- You want the car to move you from one place to another.
- The heat and sound energy are wasted energy.

Wires - heat
- When wires are used in an electrical circuit, they heat up.
- The heat produced is often not useful energy and so it is wasted.

Friction - heat
- In almost every energy transfer, friction creates heat energy.
- The heat energy is often wasted.
Test yourself on Energy Wastage
Which of these is an example of useful energy?
Which of these statements about wasted energy are true?
Perpetual machines can continue moving forever without ever stopping. Why are perpetual motion machines impossible?