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A CRITITQUE Because matter is inherently active Galileo, Newton and Einstein were able to descnbe and explain many mysteries of the universe by formulating laws of mechanics Motion of matter evolved a mechanical universe of forces, pressures tensions oscillations and waves Two fundamental forces exerted by matter are gravitation and electromagnetism Save for gravitation, nearly all other forces in the material universe-frictional forces chemical forces which hold aioms together in molecules cohesive forces which bind particles of matter elastic forces which cause bodies to maintain their shape-are of electromagnetic origin, for all these involve the interplay of matter which is composed of electrical particles
To describe the mechanics of dynamic material universe, three parameters are necessary, distance in space, time and mass 26 In classical physics the mass of any body is a fixed and unchanging property But Einstein established the relativity of mass, asserting that the mass of a moving body increases with its velocity according to the following equation, when mo is the inass of a body at rest m is its mass when moving V is the velocity of the body and c is the velocity of light
m =
mo
It can be readily seen that if v is small the difference between me and m is practically zero But when v approaches the value of c then the increase of mass becomes very great reaching infinity when the velocity of the moving body reaches the velocity of light
26 Mass is not heaviness or weight but denotes a fundamental property of matter namely resistance to a change of mouon
