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]
06.22: During an interval of time, a t d(nf bh,s )*sdjr3 io:69kcfpuqz,;w ennis ball is 8l hn+r+-ok-z)mx ysf1uz a 7emoved so that the angle between the velocity and the acceleration of the ball is kef o+rzz+)euy l-7n-ksxa8mh 1pt at a constant 120 degree. Which statement is true about the tennis ball during this interval of time?
A. Its speed increases and it is changing its direction of travel.
B. Its speed decreases and it is changing its direction of travel.
C. Its speed remains constant, but it is changing its direction of travel.
D. Its speed remains constant and it is not changing its direction of travel.
E. Its speed decreases and it is not changing its direction of travel.
参考答案: B
本题详细解析:
暂无
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