Energy & Matter FAQ's! What is matter? The water that you drink, the pencil that you hold when you write, the air that you breath are examples of matter. Matter is "everything that takes up space and has mass". What is mass? Mass is how much matter an object has. A big rock has more mass than a pebble. A tree has more mass than a bush. Can we only see and touch matter? No, you can also hear it, smell it and touch it. When you drop an object in the ground you hear matter, when you burn something you smell matter and when you eat you taste matter. What is friction? "Is the force that opposes motion". We can walk without falling because of the friction between the sole of our shoes and the ground. When is wet or icy, there is less friction and easier for us to fall down. Can friction produce heat? Yes. We can start a fire by rubbing to pieces of dry wood against each other. When we are cold, usually we rub our hands together to warm up a little bit. What does friction, matter, energy or inertia has to do with science? Physics is the science that studies friction, matter, energy, inertia and many other fields. It was not until the 19th century that physics was recognized as a separate science.