Why do things fall? It’s about force and motion. Find out more in this Science Trek short. A force is basically a push or a pull. Forces like gravity, inertia, and momentum affect everything. On ...

PhET Interactive Simulations (aCC BY-NC-SA 2.0) Tugging a small toy with your dog can be a lot of fun—but it’s also a great way to experiment with forces acting on an object. Forces are what ...

Gravity is the force of action between two objects. It’s called a natural force because it acts at a distance rather than needing to be in contact. Gravity is the force that holds us down on ...