So and unbalanced force doesn't necessarily have to impact the object's speed.

所以和不平衡的力 不一定必须改变响物体的速度。 尽管不平衡力经常会改变物体的速度。所以和不平衡的力 不一定必须改变响物体的速度。 尽管不平衡力经常会改变物体的速度。

Using the depth, which had carved into the seabed, investigators are refining their calculations of the impact speed.

调查人员正利用船在海底的深度完善他们对撞击速度的计算。

At asteroid impact speeds, kinetic energy is cruel.

在小行星撞击速度下，动能是残酷的。