The idea of force can seem complicated, and kind of slippery to get a hold on, but there is a surprisingly simple, yet extremely effective definition. A force is a push or a pull. If an object feels a push or a pull from something, it feels a force. If an object cannot push or pull on another object then it simply cannot exert a force on that object. It's that simple. A force is a push or a pull.
© 2008 Kansas State University Physics Education Research Group.