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Re: repulsive forces
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Re: repulsive forces - 10-26-2007, 04:20 PM

Quote:
Originally Posted by RascalPuff
if it were entitled 'attractive forces'?('For every action there is a reaction, equal and opposite')
Newton's 3rd law of motion is still quite enigmatic for me. The only purely attractive force is gravity. Newton never gave any good reason why there have to be two force laws: his 2nd law of inertial force and inertial mass and his law of universal gravitation for gravitational mass. As far as modern physics is concerned both inertial mass and gravitational mass are equivalent, principle of equivalence. This is the key for Einstein's theory of general relativity.


Time independence: [∂E(g)]²=[∂F(a)×∂r(a)]·[∂F(b)×∂r(b)] and Mass independence: a(tr(t)=c²
  
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