In particular, it is the first law of thermodynamics ... Leonardo da Vinci, back in 1494, said: Oh ye seekers after perpetual motion, how many vain chimeras have you pursued?

So, what are forces? Well forces cause things to change, and a beautiful example of that is Newton's first law of motion. It says that things stay still or carry on moving at a constant speed in a ...

His many discoveries include the law of inertia later used by Isaac Newton as the first law of motion, the parabola as the path of a projectile, the relationships between distance and velocity ...