题目内容

一物体质量为10 kg,受到方向不变的力F作用,在开始的两秒内,此力冲量的大小为140(SI);若物体的初速度大小为10 m/s,方向与力的方向相同,则在2s末物体速度的大小等于()(SI).

A. 14
B. 24
C. 10
D. 20

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