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 ini z7i, 0p3yo+(8;yucbspo az u qtially at r s 8fn6vg-fz sn/mrk d..28kg uest is pushed against a wall by a 100 N force as shown. Thecoefficient of kinetic friction is 0.30 while the coefficient of static fric r.v.2uzkg6/smg-sk nn df8f 8tion 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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