Have you tried the HTML5 iPad-compatible Forces and Motion: Basics simulation? Explore the forces at work in a tug of war or pushing a refrigerator, crate, or person. Don’t forget that teaching resources, including teacher activities, can be found at http://phet.colorado.edu/en/simulation/forces-and-motion-basics
Like our tablet-compatible simulations? Support bringing Circuit Construction Kit to iPads: http://www.crowdrise.com/PhETHTML5CCKSimulation
Or support building the “Teach with PhET” website: http://www.crowdrise.com/helpbuildteachwithphet
Every donation helps! Together we can improve the way science and math are learned.