On the Whirlwind ride at the fair I definitely felt pushed outward against the wall. My teacher says that’s not a real force. Who’s right?
Seen from the ground, there is no outward force at all. Your body’s inertia keeps trying to carry it in a straight line, and the wall or seat pushes you inward to bend that path into a circle; that inward push is the centripetal force. The outward “feeling” is what inertia feels like from inside the spinning ride, which is why physicists call centrifugal force a fictitious force.
Accepted answer
You both felt something real, just from different viewpoints! From the ground (an outside, inertial frame), the only real force on you is the wall pushing inward on your back - that inward push is the centripetal force keeping you moving in a circle. Inside the spinning ride (your own rotating frame), it feels like something is pushing you outward. That apparent push is "centrifugal force" - it’s a real sensation, but not a real interaction force between two objects. It only shows up because your frame itself is rotating.
Same idea powers a lab centrifuge and a salad spinner: spin something fast enough and the "outward" effect in the spinning frame is strong enough to separate liquids or fling off water.