本题目来源于试卷: 美国2021年物理杯赛真题 PHYSICS BOWL 2021，类别为 美国物理杯赛(Physics Bowl)
[单选题]
Two balls, A and B, are launched simultaneously from theorigin (O) on a level surface at the respective angles of 60°and 30° shown in the picture. Ball A has a launch speed vwhile Ball B has a launch speed 2v. Ball A lands T seconds after launch at a horizontal distance D from the origin. How many seconds after launch does Ball B land?
A. 0.50T
B. 0.87T
C. 1.15T
D. 1.73T
E. 2.00T
参考答案: C
本题详细解析:
$T_A=0.174v \; T_B=0.202v$; $\frac{T_B}{T_A}=1.15$
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