Monday, 6 January 2014

Laws Of Motion

 

Laws of Motion discovered by Newton , They are as follows ;

Law 1  :-     Every body  perseveres in its state of rest or of uniform motion in a straight line unless it will compelled to change that state by impressed force .

Law 2  :-     The rate of change of momentum is proportional to the impressed force and take place in the direction of the straight line in which the force acts .

Law 3  :-     To every section there is always an equal and opposite reaction or the mutual action of any two bodies are always equal and oppositely directed .

The first law implies :

1)-----  That the internal force in a body do not play a part in the state of rest or of uniform motion .

2)-----  The definition of an external force as that which tends to change the inertia of a body on which it acts .

The second law enables us to measure force . If a mass    m     moves with a velocity    v     then its momentum is   mv     .

According to second law ;

F  (an external force)   varies as     (d/dt) (mv) 

therefore   F=K.(d/dt)(mv)  where   K   is a suitable constant

                  =K.m.dv/dt  ,  if    m   is a constant .

                  =K.m.f  ,  where    f    is the acceleration .

We now define a unite of force as that force which acting on unit mass produces unit acceleration .

therefore    1=k.1.1  so that      K=1.

therefore     F=mf

                     = mass .  acceleration    .


No comments:

Post a Comment

Our Latest Post

Introduction of Circle

All of my lessons and teaching videos are in English and most of them are for students of Logistics Management. But many of mys students an...

Popular Post