Dear Sirs,
1, 2, 3 laws of Newtons need closed system (net force is zero). How do we practically realize, create such closed system?
One example. Let us look at a body motion. One can say If the body velocity is constant, e.g. zero then no forces act to it. Is it true? I think no. According to the 1st Newton law the velocity constance is the CONSEQUENCE of F=0.
So are there precise ways to construct closed system? Or all physical theory is just a mean to generate a hypothesis which has more higher probability to be true then other random thought?
I do not go into the complete question, and consider only one aspect of it. Begin with Newton's second law, namely
(1) F = m a,
where F is force, m mass, and a acceleration. Let t denote time and v(t) velocity as function of time, so that
(2) a(t) = ∂v(t)/∂t.
From (1) and (2) it follows that (integrating a first-order differential equation)
(3) v(t) = v(0) +(1/m) ∫0t dt' F(t').
From this equality it follows that for F(t) ≡ 0, v(t) ≡ v(0), independent of t. Clearly, for v(0) ≡ 0, in this case one has v(t) ≡ 0 for all t. Thus, from Newton's second law we have arrived at Newton's first law. Note that when v(t) ≡ v(0) for arbitrary t, Eq. (3) implies F(t) ≡ 0. □
Sections I, VII, and VIII in this paper deal with the inertial frame of reference. It's all about analyzing the deeper physical basis that underlies the inertial forces
Article The Double Helix and the Electron-Positron Aether
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