What Is Energy?
Energy is one of the most important ideas in all of science. It explains why things move, why things heat up, why living things grow, and why machines work. But what exactly is energy?
Energy is the ability to do work — to cause a change or make something happen. Energy cannot be created or destroyed, only transferred from one form to another.
Think about your morning routine. When you eat breakfast, the food gives you energy to move around. When you turn on a light, electrical energy becomes light and heat. Everything that happens in the universe involves energy in some form.
Scientists measure energy in units called joules (J), named after the physicist James Prescott Joule.
Think of energy like money in a bank account. You can move it between accounts (transfer it), spend it on different things (convert it to different forms), but the total amount always stays the same — it never disappears!
The Main Forms of Energy
Energy comes in many different forms. In MYP 1, we focus on three key forms:
- Kinetic energy — the energy of movement
- Potential energy — stored energy, ready to be used
- Thermal energy — the energy related to heat and temperature
These three forms are linked to almost every event you can observe in daily life — a rolling ball, a stretched rubber band, a warm cup of cocoa. Understanding these forms helps you explain why and how things happen around you.
There are other forms of energy too — such as light energy, sound energy, chemical energy, and electrical energy. These are explored further in later MYP years. For now, we focus on kinetic, potential, and thermal energy as our starting point.
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