Coriolis Force, Page 2 of 4
Motion relative to a fixed reference frame: The path that the thrown ball takes is a straight line, as you can see. However, consider the ball leaving marks on the rotating carousel as it moves. The marks describe a circular pattern. The motion of the ball obeys Newton’s law because it does travel in a straight line relative to the “inertial” reference system.
What you should notice:
- The ball travels in a straight line in the “inertial frame”, which is indicated by the green background and the person sitting on the bench at the right.
- The ball motion as seen by the figures rotating with the carousel is seen to be curved, as indicated by the yellow dots.