本题目来源于试卷: Newton’s law of motion,类别为 美国物理杯赛(Physics Bowl)
[单选题]
04.40: A 6.0 kg block initially -,wyaeq8c: tx2t jd68aza pm j+awh;6at rest is pushed against a w wf p 035w73b/1+dphyec2ptipb en7 qcm /+uzfall by a 100 N force as shown. Thecoefficient of kinetic fr phpfb b/yp7ww1e2/7m i ztn5 33 0e++cfuq dpciction is 0.30 while the coefficient of static friction is 0.50. What is true of the friction acting on the block after a time of 1 second?
A. Static friction acts upward on the block.
B. Kinetic friction acts upward on the block
C. No friction acts on the block
D. Kinetic friction acts downward on the block.
E. Static friction acts downward on the block.
参考答案: D
本题详细解析:
暂无
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