Did you know that, at a certain point on a moving wheel... there's no motion? Did you know that, at a certain point on a moving wheel... there's no motion? I mean, kinda... it's all relative, right?

Why study physics, you ask? Scroll down, friend. This video of a guy rolling through a 360-degree vertical loop at a skatepark—cool as ice, with no helmet—is answer enough. Clearly, his understanding ...

When an object changes velocity, it accelerates. Acceleration is the change in velocity per second and is measured in m/s 2. Acceleration is a vector quantity because it has size and direction. The ...