本题目来源于试卷: gc physics textbook chapter 6 problems，类别为 IB物理学
[问答题]
A bowling ball is hun y/(dxs thr 4ga.f44wbg from the khylh4)i7;v9 h sgz*q.czv j0 ceiling by a steel wire (Fig. 6–33). The instructor pulls the ball back and stands against the wall with the ball against his nose. To avoid injury the instructor is supposed to relea h kyvh74)l j *vc; i9z0qzgsh.se the ball without pushing it. Why?
参考答案:
If the instructor releases the ball without
pushing it, the ball should return to exactly the same height (barring any
dissipative forces) and just touch the instructor’s nose as it stops. But if the instructor pushes the ball, giving
it extra kinetic energy and hence a larger total energy, the ball will then
swing to a higher point before stopping, and hit the instructor in the face
when it returns.
本题详细解析:
暂无
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