Physics4kids
Physics 4 Kids: Mechanics and Motion
Motion is one of the key topics in physics. Everything in the universe moves. It might only be a small amount of movement and very very slow, but movement does happen. Don't forget that even if you appear to be standing still, the Earth...
Physics4kids
Physics 4 Kids: Where Traditional Physics Stops
We're about to move into the modern age of physics. In the early 1800's, scientists began examining the basis of matter, space, and time. Sometimes it gets very confusing, but the big idea is that Newton's physics describe about 90% of...
NASA
Nasa Star Child: What Is a Light Year and How Is It Used?
This is a definition and example of how distance is measured in astronomy, such as the distance between our earth and the stars.