Mechanics / Electrodynamics
May 25, 2021
Newton has stated the third law of motion in the Principia in 1686 i.e. 335 years before. The emergence of new technologies have changed the scientific understanding. Thus Newton’s law is being discussed in view of rockets, bouncy balls ( super ball and sky ball), experiments regarding shapes of bodies etc. Newton’s law is equally applicable in all such discoveries. Rockets move forward as exhaust (flame, fire, gases , sparks smoke etc.) moves in the backward direction. Whereas electric aeroplanes, solar driven planes do not emit any exhaust , thus their motion is not consistent with third law of motion. In addition the shape of bodies, characteristics of bodies etc. play significant role when bodies rebound. The law of conservation of momentum also follows from third law of motion when bodies collide. The law can be tested in this form as discussed. Consequently the third laws theoretically extended. If experimental results are not consistent with original form of Newton’s third law of motion, then extended form ( Reaction = -Q Action, where Q is coefficient of proportionality) will be useful. The discussion is in Question-and-Answer form for simplicity .