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]
A projectile will be launched from a 2.00-m tall platform and must hit a target at ahorizontal distance of 25.0 m away on an identical 2.00-m tall platform. What is the slowest speedat which the projectile can be launched?
A. 10.2 m/s
B. 12.5 m/s
C. 15.8 m/s
D. 17.7 m/s
E. 21.0 m/s
参考答案: C
本题详细解析:
$x=\frac{v_0^2sin2Θ}{g}$;maximum range achieved at launch angle of 45° .
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