A hypothesis is a specific, testable prediction about what you expect to happen in your study or experiment. For example, you might have the hypothesis: ‘If plants are given more sunlight, then they will grow taller than plants that receive less sunlight.’
This hypothesis is testable because you can design an experiment where one group of plants receives full sunlight while a second group receives partial sunlight. By measuring the height of the plants over time, you can determine if your hypothesis is supported or refuted based on the data you collect.
A good hypothesis not only states what you think will happen but also provides a rationale for your prediction. In this case, the rationale might be that sunlight is essential for photosynthesis, which is crucial for plant growth.