CK-12 Foundation
Marie Curie's Classroom
What makes some elements stable and others radioactive? Scholars adjust the number of protons and neutrons in an element then observe its decay. The simulation includes a graphical representation and the chemical formula, as well as...
CK-12 Foundation
Magnifying Glass
How can a magnifying glass or reading glasses make things appear larger? Scholars simulate moving a lens closer or farther from an object to observe the resulting image. They also alter the lens focal length. The simulation shows the...
CK-12 Foundation
Block and Tackle
Can you easily lift more than your own weight? With a pulley system, almost anyone can manage this challenge. Scholars adjust the mechanical advantage (number of pulleys), weight of object being lifted, and the length of rope pulled. The...