Theory - GCSE Physics Definition

In GCSE Physics, a 'theory' is an idea or set of ideas that explains how something in the world works. It is based on observations, experiments, and evidence collected by scientists. Once a theory is developed, it helps us understand natural events or predict what might happen in certain conditions. For example, the theory of gravity helps us explain why objects fall to the ground. Even though theories are well-tested and widely accepted, they can be updated or changed if new evidence is found. So, a scientific theory is a reliable explanation but also open to improvement as we learn more.