CENTRE OF GRAVITY

CENTRE OF GRAVITY :-

                Gravititional id defined as the fore of ataction between two defined as the force of attraction between two bodies of this inverse , where as the force of direction between the earth and any other body is called gravity and gravititional force. the force, by which a body attracted towards earth is called weight

@ Newton law of gravitation :-

     all bodies attact each other and the force of attraction between them is directly proportional to the product of their masses and is inversely proportional to the the square root of radius between them

@ Centre of gravity :-

       Each body is made up of very large number and small particles . which are attraced towards the centre of earth by force of gravity . this gravity force with which a particle is attracted towards the earth is called weight of the particle
                  thus, weight of each particle as a force will be acting vertically towards. since all these parellel forces are acting in same direction , their resultant us equation to sum of all of them such a point is called centre of gravity

@ Some important facts :-

                 i) Each body has only one center of gravity
 ii) Centre of gravity is independent on a body
iii) the centre of gravity well depend upon shape of the body
iv) the centre of gravity is an imaging point which may or may not be with in boundry of the body

@ centre of area or centroide :-

        it is defined as two point where the whole area of a object is assumed to be concentrated

@ Difference between center of gravity centriode :-

- The term centroid is used for plain . which have only area but no mass where as the terms centre of gravity used for solid bodies having mass
- the terms center of gravity can also be used in place of centroid of plane . since every plain has one only one center of gravity , which  concides of plain, however the terms centroid can not be used in place of center of gravity of solid body because a solid body can be split up into amembelaminas. in actual pracice centre of gravity and centroid are  same

@ Cenroiled axis :-

           the axis passes through the centroid threw the centroid of a plain figure and perpendicular to each other are called centroid ais

@ axis of referance :-

                    the center of gravity of a body is always calculated with referance to same a sum of ais known as axis of referance
            the axis of referance of plain figure is generally  taken lowest line of figure for calculating x (bar) and extreme left line of the figure the calculating Y (bar)

@ Center of garvity - centroide in figure by method of moment :-

                           i) place the hall in 1 (a), draw the x-axis threw . the bottom most line y-axis threw axis left line
ii) Divide the composite secion into simple square, triangular etc
iii) calculate the area A1, A2 ,A3, A4 of each cpmponents
iv) Also calculate the distances of centroid of area A1, A2, A3 fom the respective referance
v) Then find the center of gravity of given compositive section