Equations of motion system). Particle does not exert a torque on itself. Some examples of Newton's law include describing the motion of a simple pendulum, and a damped, sinusoidally driven harmonic oscillator, For describing the motion of masses due to gravity, Newton's law of gravity can be combined with Newton's second law. For two examples, a ball of mass thrown in the air, in air currents (such as wind) described by a vector field of resistive forces , where is the gravitational constant, the mass of the Earth, and is the acceleration of the projectile due to the air currents at position and
Perpetual motion what he believed to be impossible: Some common ideas recur repeatedly in perpetual motion machine designs. Many ideas that continue to appear today were stated as early as 1670 by John Wilkins, Bishop of Chester and an official of the Royal Society. He outlined three potential sources of power for a perpetual motion machine, " Extractions", "Magnetical Virtues" and "the Natural Affection of Gravity". The seemingly mysterious ability of magnets to influence motion at a distance without any apparent energy source has long appealed to inventors. One of the earliest examples of a magnetic motor was proposed by Wilkins and