What is tension? How do you calculate tension? This site will review over how ropes pull on things and how to handle that kind of force.

If you have ever run into a solid wall, you have experienced the pain of a normal force. This webpage reviews over the force exerted when two objects touch.

Learn about the force of friction on this reference page which defines why friction is important and how it can change physic problems.

A webpage with equations and examples of how to solve inclined planes problems. Learn how to deal with slopes when surfaces usually aren't perfectly horizontal.