Why does a rock sink in water while a gigantic steel aircraft carrier floats? The aircraft carrier is much heavier, but glides along the ocean surface with ease. Clearly, weight isn’t the entire story ...
Every day, the Sun rises in the east, rides across the sky, and sets in the west. Once upon a time, people thought gods like Apollo carried the Sun on a chariot. But as it turns out, the Sun doesn’t m ...
An Atwood Machine is a very simple device invented by George Atwood in 1794 as a way to demonstrate Newton’s Laws of Motion. Newton’s Second Law of Motion says that the force required to move somethin ...
The movement of a pendulum is called simple harmonic motion: when moved from a starting position, the pendulum feels a restoring force proportional to how far it’s been moved. Put another way, it alwa ...
Friction is kind of a drag. Every time you push on something, friction pushes back. To get an object moving, you have to overcome the friction force first. If you’ve ever walked on pavement and sudden ...
If space is a vacuum—that is, if it contains absolutely nothing—then how does a rocket move? Doesn’t it need something to push against?Rockets can propel themselves through the nothingness of space be ...