At the end of the day, most of the newtonian physics as we know it in classical mechanics is relatively accurate for small bodies of motion. Yet such Newtonian models of force, speed and distance is negated when it concerns very large and massive bodies. For example, planets, stars, galaxies and other universally large constants of motion. In such cases, we must consider the time lapse variable generated by the effect of gravity.
As a real world example, most GPS satellites would give our locations wrongly by a few miles if they were not corrected by Einstein's General Theory of Relativity where the interaction of gravity, energy, mass, space and time affects each other simultaneously.
Indeed, Classical Mechanics has been superseeded by Quantum Physics and Mechanics. For the newtonian model of F = GmM/r^2, it is invalid in the determinant of Mercury's orbit and revolution upon its axis due to the effects of time warp from the Sun. Thus we must be careful to note that what was taught to us during college days as well as first year undergraduate physics be taken with a pinch of salt at the higher levels.
Then again, no doubt, the newtonian model is much simpler to understand, apply, use and to calculate from. The Einsteinian methologies exemplify extremely complex and complicated mathematics of at least graduate level stretching to post-Doctoral level.
And at the end of the day. It is concluded that out of every student that took physics in secondary school and JC. 99.5% dislike the subject.
