本题目来源于试卷: Space Time & Motion A.2 Forces & Momentum，类别为 IB物理学
[单选题]
The graph below shows the variation of th wpgk kvcq,k o,f/( 2lv83;sofe 8g1z65q jxs vmkat,nx k089ke resultant force $F$ acting on a box with time$t$.
The box starts to move from rest. Which of the following graphs shows the variation of the momentum $p$ of the box with time $t$?
A.
B.
C.
D.
参考答案: A
本题详细解析:
Explanation:
The area underneath of the force-time graph gives the change in momentum of the box. Since the area increases with time at a constant rate, the momentum should increase at a constant rate. The only graph that satisfies this condition is the graph in A. Therefore, the answer is A.
Alternatively, the impulse equation gives
$\Delta p = F \Delta t$. As $F$ is a constant, $\Delta p$ is directly proportional to $\Delta t$ and a straight line through the origin is expected.
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