A 2.40- bullet embeds itself in a 1.20- block,which is attached to a spring of force constant 770 .

问题描述:

A 2.40- bullet embeds itself in a 1.20- block,which is attached to a spring of force constant 770 .
If the maximum compression of the spring is 5.60 ,find the initial speed of the bullet.
Find the time for the bullet-block system to come to rest.

都没单位啊……
题目大致意思就是一枚子弹打进一块砖头里,砖头放在一个喷泉上,喷泉提供770的恒力,喷泉的最大压缩为5.6,计算子弹的初始速度,以及系统恢复静止的时间
题目就这样,没单位的话没法算……