Relative size refers to the comparison of the size of one object to another. It helps us understand how large or small something is in relation to something else. For example, when comparing the Earth to the Sun, the Sun is much larger, illustrating the concept of relative size in the solar system. This concept is also used in everyday life. For instance, when looking at a mouse next to a cat, the mouse appears smaller. Understanding relative size can help us visualize and comprehend the dimensions of objects in our environment more effectively.