Here are some examples of physical changes:
* Changes in state: Melting ice (solid to liquid), boiling water (liquid to gas), freezing water (liquid to solid) - the chemical makeup of water (H2O) remains the same.
* Changes in shape: Folding a piece of paper, cutting a piece of cloth, breaking a glass - the material itself is still the same, just in a different form.
* Changes in size: Stretching a rubber band, crushing a can, compressing a gas - the molecules within the material haven't changed.
* Mixing: Adding salt to water, stirring sugar into coffee, making a salad - the ingredients are still the same, just mixed together.
Important to note: While a physical change doesn't alter the composition of a substance, it can sometimes be difficult to reverse. For example, once a piece of glass is broken, it's hard to put it back together.
