本题目来源于试卷: gc physics textbook chapter 4 problems，类别为 IB物理学
[问答题]
When you stand still/ )xfqiutk um +2y0gq0 l8:bwme7r n)qd:d z76th j.tion the ground, how large a force does the ground exert on you? Why doesn’t this force make you rise up 7 t6i7. ::bndwd8lh)qz mtjreinto the air?
参考答案:
If you are at rest, the net force on you is zero. Hence the ground exerts a force on you exactly equal to your weight. The two forces acting on you sum to zero, and so you don’t accelerate. If you squat down and then push with a larger force against the ground, the ground then pushes back on you with a larger force by Newton’s third law, and you can then rise into the air.
本题详细解析:
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