# Circular and Satellite Motion - Mission CG3 Detailed Help

 Suppose you go with your friend on a roller coaster ride. After the ride, your friend describes the 'awesome outward pull on the second loop.' Such a statement only proves that your friend ____.
 Definition of Inertia: Inertia is the property of an object that describes its natural tendency to keep on doing whatever it is doing.
 We could probably say a lot of nice things about your friend that are true. But from the comment that he/she just made, we must say that there is a shortage of understanding concerning the physics of circular motion. A force is a push or pull exerted upon an object. There is no such outward pull exerted on your friend when traveling through a roller coaster loop. The sensation of being pulled outward is simply the tendency of an object to naturally continue in a straight line tangent to the curve of the loop. Straight line motion does not require a force; it's simply the thing an object naturally does in the absence of a force. To move along the curve of the loop, there must be an inward force upon your body. While you and your friend might be pushing the seat outward, the seat is actually pushing you in an inward direction. Circular motion requires an inward force.