What is the difference between apparent weight and true weight?
Your true weight is caused by gravity—it is the force exerted on you by gravity; usually the earth’s gravity. Your apparent weight is the sum of your true weight and a fictitious force associated with your acceleration. Whenever you accelerate, you experience what feels like a gravitational force in the direction opposite your acceleration. Thus when you accelerate to the left, you feel a gravity-like experience toward your right. It is this effect that seems to throw you to the right whenever the car you are riding in turns toward the left. In fact, this effect is caused by your own inertia—your own tendency to travel in a straight line at a constant speed. Your apparent weight can be quite different from your true weight. Perhaps the most striking example occurs on the loop-the-loop of a roller coaster. While your true weight remain downward throughout the ride, as it always is, your apparent weight actually becomes upward as you pass around the top of the loop-the-loop. You are accelerating downward so rapidly at the top of the loop that the experience you have is one of a gravity-like force that is pulling you skyward. Since the car you are riding in is invert and above you, you feel pressed into your seat even though the ground is in the other direction.