本题目来源于试卷: Space Time & Motion A.1 Kinematics，类别为 IB物理学
[单选题]
A student throws a ball with an inip4f l / ysuu+/uvugeo.w6u8g,tial velocity innzm(/e6 (w 5hzyo4li wy)l6bq the horizontal direction. Air resistance is negligible. At t=2.0 s, the ball has travelled a distance x in the horizontal direction and lo/iw5hqb )mlyn6 e6((y wz4za distance y in the vertical direction.
What are the horizontal and vertical distances covered at t=1.0 s, in terms of x and y?
A. Horizontal distance is $\frac{x}{2}$;Vertical distance is $\frac{y}{4}$
B. Horizontal distance is $\frac{x}{2}$;Vertical distance is $\frac{y}{2}$
C. Horizontal distance is $\frac{x}{4}$;Vertical distance is $\frac{y}{2}$
D. Horizontal distance is $\frac{x}{4}$;Vertical distance is $\frac{y}{4}$
参考答案: A
本题详细解析:
Explanation: Horizontal velocity is constant, therefore, the distance travelled will be half in half the time. Vertical height is proportional to $t^2 (s=0.5 at^2) $ therefore in half the time, a quarter of the height will be reached.
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