Veronica observes how the force of friction causes an object to slow down. She writes the following observation: When an object
moves across a smooth surface, there is less friction created than when an object moves across a rough surface. When the object stops moving, friction is created. Which statement corrects the error(s) in Veronica's observations? It is not smooth or rough surfaces that affects friction. It is the size of the push.
When an object moves across a rough surface, there is no friction.
When an object moves across a smooth surface, the friction increases.
When an object stops moving, there is no friction.
<span>The best reason I can think of for why we believe that air is a mixture is that freezing air slowly yields different liquids at different temperatures. Liquid nitrogen has a different boiling point than liquid oxygen. They also freeze at different temperatures. If air were only 1 compound, then air in its entirety would have a single boiling point and a single freezing point. </span>
