As a result, any object in free fall near Earth's surface accelerates at 9.81 m/s/s. The gravitational force acting on an object is not always equal to its weight. A free falling object experiences a ...

If you drop an object, it will fall. It's a motion that we’ve all seen hundreds of times. We’ve also all seen plenty of the moon, which makes one complete orbit around our planet every 27.3 days (as ...

Our motion perception is remarkably well tuned to detect small changes in speed and direction. For example, soccer goalkeepers need to precisely judge the speed, direction, and curvature of an ...