Whenever there is a change in the physical state of matter such as size or shape it is called a physical change. In a physical change, no new substance is formed. And when there is a change in the chemical properties of a substance as a result of which a new substance gets formed, a chemical change occurs.

Here, when ice melts it transforms from solid to liquid, so, there is a change in its physical state but there is no change in its chemical composition. Thus the change is a physical change.