帮帮我物理的英语，应该选哪个？

更新时间2019-10-02 01:09:00

——— If the forces that act on a cannonball and the recoiling cannon from which it is fired are equal in magnitude, why do the cannonball and cannon have very different accelerations?

A). The force from the cannon ball on the cannon produces little acceleration because it lasts for such a brief time.

B). Remember F = ma, and note that the cannon has a much greater mass than the cannon ball, so the cannon accelerates less for the same force.

C). The cannon weighs so much that friction with the ground alone prevents it from accelerating.

D). The cannon pushes on the cannon ball with a much greater force than the cannon ball pushes on the cannon.

帮忙一下

If the forces that act on a cannonball and the recoiling cannon from which it is fired are equal in magnitude, why do the cannonball and cannon have very different accelerations?如果作用在炮弹上的力和用来发射炮弹的反冲炮的力大小相等，为什么炮弹和大炮的加速度有很大的不同呢?

A). The force from the cannon ball on the cannon produces little acceleration because it lasts for such a brief time.A).炮弹对加农炮的作用力产生的加速度很小，因为它持续的时间很短。

B). Remember F = ma, and note that the cannon has a much greater mass than the cannon ball, so the cannon accelerates less for the same force.B).记住F = ma，并注意加农炮的质量比炮弹大得多，所以在相同的力下加农炮的加速度更小。

C). The cannon weighs so much that friction with the ground alone prevents it from accelerating.大炮很重，仅与地面的摩擦力就使它无法加速。

D). The cannon pushes on the cannon ball with a much greater force than the cannon ball pushes on the cannoD).火炮对炮弹的推力比炮弹对罐头盒的推力大得多。

综上可知，我认为应该选 B 。