Bill Nye The Science Guy Season 3 Episode 3

Plants

The momentum of a moving thing, like you riding your bike, depends on how much mass you and your bike have and how fast you’re speeding down that hill. An elephant on a bike has more momentum than a mouse on a bike moving at the same speed. A mouse on a fast bike has more momentum than a mouse on a slow bike. If there’s an elephant on a fast bike, you’d better get out of the way.