[] 相対性理論はインチキだろう.
168. 2023年1月12日 16:45:36 : NQvpzvOMZI : RTNPZmNhVFRLci4=[1]
Newton's Third Law of Motion　(クリ)

A body of mass m is suspended from ceiling by a string. From below, this body is pulled by another string. Tension of this string is 2 mg. So, the tension of upper string is 3 mg. That is, action-reaction of upper string is both 3 mg. Mass of the body is basically irrelevant.

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