Some forces are called contact forces because they require objects to touch. One is tension force, found in stretched wires. Another is the force found in a spring. And last are resistive forces: ...

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 Earth and ...

If your students like sports, rockets and roller coasters, then they’ll like Sir Isaac Newton! Newton’s Laws will help your students understand force, motion, and the transfer of energy. In this ...