Live interactive physics simulations let you explore the Solar System (orbits, seasons, gravity, tides, satellites and comets), play snooker (on a full size table) and experiment with Laws of Motion simulations (free worksheets provided for pendulum, Newtons cradle, terminal velocity and Galileos balls - as dropped from the Leaning Tower of Pisa) - latest release includes machines ( pendulum clock and siege engines) bridge, crash and ideal gas simulations and experiments. With real-time visualisation of forces and velocities (as arrows on each object as they interact or are pulled around with the mouse) and scrolling graphs recording what happens, MaterialWorlds gives a real feel for how the physical world works.