Ajay Sharma. Int. Journal of Engineering Research and Application www.ijera.com ISSN: 2248-9622, Vol. 8, Issue 1, ( Part -IV) January 2018, pp.66-71 www.ijera.com DOI: 10.9790/9622-0801046671 66 | Page The third example of Newton’s Third Law leads to inconsistent results i.e. mass becomes infinite and imaginary. Ajay Sharma Fundamental Physics Society. His Mercy Enclave Post Box 107 GPO Shimla 171001 HP. India. ABSTRACT Objective: Newton gave three examples to explain illustrate the law after definition. The first two examples, a stone is pushed by finger or a stone is pulled by horse. Their critical study leads to inconsistent study. Methods/Statistical analysis: Newton considered in two cases that forces are so applied the stones remain at rest. Thus work done is zero (W=F.0 =0). Whereas in third case Newton considered example of collisions that bodies moves after they collide. Newton further stated that change in momentum of projectile is negative of change in momentum of target. Findings: Thus velocity of target can be measured from equations third examples. In many cases the velocity of the target turns out equal to c or more than c (speed of light). Thus relativistic mass becomes infinite and imaginary. This is clear inconsistency between experimental findings and theoretical deductions. Application/Improvements: In physics adhoc assumptions (as in case of Michelson Morley experiments) and empirical determination of coefficient (Bethe–Weizsäcker mass formula) is taken up. In view of these if statement of Newton’s is regarded as in proportionality form. Then of coefficient of proportionality is regarded as less than unity i.e. ½ (say), then consistent results are produced. --------------------------------------------------------------------------------------------------------------------------------------- Date Of Submission: 12-01-2018 Date Of Acceptance: 03-02-2018 -------------------------------------------------------------------------------------------------------------------------------------- I. INTRODUCTION Earlier Newton defined third law of motion in the Principia (1686) at page 20. The original form of the Third Law of Motion as in the Principia[6] is: To every action there is always opposed an equal reaction; or the mutual actions of two bodies upon each other are always equal, and directed to contrary parts , Action = - Reaction (1) or Action of first body on second = - Reaction of second body on first (1) or Force exerted by one body = -Force exerted by other body (1) F A =- F B There is no other term between F A , F B thus forces exerted by bodies are not affected by any other factor. Thus action should always be equal to reaction. Thus action and reaction has to be always equal or force exerted by Body A on Body B must be UNIVERSALLY equal. But experimentally this deduction is not justified along with other deductions from the law. These can be easily justified. Newton justified the law in the Principia. Newton further stated the third law of motion in different ways i.e. in terms of action and reaction; and force exerted by body A (F A ) on the body B (F B ) of body A . Newton’s justification of Third Law of Motion. After the statement of law Newton gave three applications of Third law of motion in qualitative way. The first two examples follow from the following statement or phrase given by Newton. “Whatever draws or presses another is as much drawn or pressed by that other. If you press a stone with your finger, the finger is also pressed by the stone. If a horse draws a stone tied to a rope, the horse (if I may so say) will be equally drawn back towards the stone” 1.1 Newton’s First example : If you press a stone with your finger, the finger is also pressed by the stone. Thus if a stone is pressed by finger, then finger also presses the stone. If pressing of stone by finger is action, then pressing of finger by stone is reaction. Finger presses the stone (action) = - Stone presses the finger (reaction) Now Newton considered the case that stone remains at rest when pressed by finger. The stone does not move at all. In this case work done is zero, as stone does not move. W =FS =0 (2) 1.2 Newton’s second example: If a horse draws a stone tied to a rope, the horse (if I may so say) will be equally drawn back towards the stone. It is again the similar interpretation. If horse pulls the stone, then horse is also pulled backward with RESEARCH ARTICLE OPEN ACCESS