本题目来源于试卷: Physics Bowl by Topic 2: Kinematics - part I General Motion，类别为 美国物理杯赛(Physics Bowl)
[单选题]
05.34: A 40-kg boy is stationary on a 30-kg plank that is sli 7 rw dw(h*0skal1f(muding at1s:38 vsv: pzwdxdk8f 5.00 m/s to the right across a frictionless pond. The boy then turns and starts walking on the plank at a rate of 4.00 m/s to the left, relative to the plank. vzxksfd8 :3wd 8:1s pvWhat is the speed of the plank relative to the pond now?
A. 1.00 m/s
B. 6.08 m/s
C. 7.29 m/s
D. 9.00 m/s
E. 17.00 m/s
参考答案: C
本题详细解析:
暂无
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