I have to wait at time capital T so that ω·T is 2π.

我必须等待时间 T 使得 ω·T 变为 2π
Because that's when the cosine returns to 1

那时余弦的值变为1
That means the time that you have to wait is 2π over ω

也就是说等待的时间是 2π 除以 ω
Or you can say ω is 2π over T,

即 ω 是 2π 除以 T
or you can also write it a 2π times frequency,

或者写成 2π 乘以频率
where frequency is what you and I would call frequency,

这里的频率就是我们所说的频率
how many oscillations it does per second.

即每秒钟振动的次数
That's the inverse of the time period.

它是周期的倒数
So, if you pull a mass and you let it go,

如果拉动并释放这个物体
it oscillates with a frequency

它有一个振动的周期
which is connected to the force constant and the mass.

与劲度系数和物体的质量有关
If the spring is very stiff and k is very large, frequency is very high.

如果弹簧很僵硬 k 很大频率就很快