Did Newton accidentally reverse the order of his laws of motion? The 1st law implicitly established the notion of time and conservation of energy. The 3rd law formulated the conservation of linear momentum by(adsbygoogle = window.adsbygoogle || []).push({});

[tex] m_1v_1 + m_2v_2 = constant [/tex]

the time derivative of this expression is

[tex]m_1a_1 + m_2a_2 = 0 [/tex]

acceleration is defined 1st before the inertial force as stated in the 2nd law.

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# Newton's 2nd law is really the 3rd law?

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