How Does GCSE Physics - Efficiency | Energy & Power (2026/27 exams) Work?

Efficiency is like how well your toy car uses its battery to zoom around the room, the less energy it wastes as heat or noise, the better it does.

Energy is the power you use to make things happen. Think of it like the amount of food you eat before playing. Power is how fast you use that energy, like eating a big meal quickly versus slowly.

Imagine you have two toy cars: one uses its battery really well, and the other wastes a lot of energy as heat (like your hands getting warm when you hold a hot chocolate). The first car is efficient because it turns most of its energy into motion, that’s what makes it zoom faster or farther.

Efficiency is calculated like this:

• Take how much energy is used for useful work (output) and divide it by the total energy used (input).
• If a toy car uses 10 units of energy and only 8 go into moving, its efficiency is 8 out of 10, or 80%.

In real life, like with your phone or a lamp, being efficient means using less power for the same job. That helps save battery, just like how you can play longer if you use energy wisely!