本题目来源于试卷: Physics Unit6: Work and Energy，类别为 通用国际物理
[单选题]
An 800-N box is pushed up anp wig.j (lq8i5 inclined plane. -uj,tzqddjpm7)* a eo)gg l/ 8The plane is 4.0 m long and rises 2.0 m. It requires 3200 J of work to get the box to the tojlzmd ,p-*q 8djgt )e )u/7ogap of the plane. What was the magnitude of the average friction force on the box?
A. $0 \; N$
B. non-zero, but less than 400 N
C. $400 \; N$
D. greater than 400 N
参考答案: C
本题详细解析:
暂无
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