And then we have c, the speed of light, 2.998 times 10 to the 8 meters per second.
然后我们知道光速等于,2,998乘以10的8次方米每秒。
So, if something cycles through five wavelengths in a single second, we would just say that the frequency of that wave is five per second.
如果一个东西在一秒,内经历了五个波长,我们就说这个波的,频率是每秒5次。
You get 2.18 times 10 to the plus 6 meters per second, 1% which is about 1% of the value of the speed of light.
。18*10^6米每秒,得到的速度大概是光速的。
It's something I throw up has an initial speed of 10 meters per second.
抛出物体的,初速度是10米/秒
It is the only region that responses to 100 spikes per second.
这是唯一以每秒钟100次做出反应的区域。
It did a million operations per second.
它能每秒运算1百万次。
So, if we have a high intensity, we're talking about having more photons per second, and it's important to know also what that does not mean.
所以,如果我们有一个高强度,我们就是在讨论每秒钟,有更多的光子数,同样理解它不代表什么,也是很重要的。
We don't usually do our chemistry calculations in miles per hour, so let's switch that to 42 meters per second, so it's -- sorry, it's 94 miles per hour.
在化学计算中我们很少,用英里每小时,所以我们把它换算为42米每秒,对不起,它是94英里每小时。
Occasionally, you'll find you need to cancel out units, because, of course, you're always doing unit analysis as you solve your problems, and sometimes you'll need to convert joules to kilogram meters square per second squared.
偶然地,你会发现需要消除单位,因为在解题时,经常要做单位分析,所以有时候需要把,焦耳换做,一千克乘以米的平方除以秒的平方。
But in terms of SI units, which become much more useful if you're actually trying to use intensity in a problem and cancel out your units, we're just talking about joules per second is what intensity is.
但是用国际单位制,这个变得越来越有用了,如果你实际上在使用强度,来解决问题和约化单位,我们仅仅讨论每秒钟的焦耳,这就是强度。
If the units come out in meters per second, you will quickly discover that the problems in 3.091 are just not that complicated.
如果你的单位是米每秒,你会很快发现,在3。091中的题目并不复杂。
So, if we kind of think about the numbers we would need, we would actually need a velocity that approached something that's about 10 to the negative 30 meters per second.
所以如果我们稍微想想,我们需要的数值是多少,我们需要一个,大约为10的负30次方米每秒的速度。
If the units are supposed to come out in meters per second and you get seconds per meter, what do you figure the chances of that problem being right are?
因为如果单位本应该是米每秒,但你写的是秒每米,你认为这个题目,还有正确的机会吗?
A joule is a kilogram meter squared per second squared.
一个焦耳等于,一千克乘以米的平方除以秒的平方。
So, the way to measure force is in kilogram meters per second squared.
所以,力的单位是千克米每秒平方
The one thing you want to keep in mind though is that Hertz does not actually mean inverse seconds, it means cycles per second. So, if you're talking about a car going so many meters per second, you can't say it's going meter Hertz, you have to say meters per second.
写成5每秒,或5赫兹,你们要记住的是赫兹,并不等于秒的倒数,它是每秒的循环数,如果你们说,一辆车一秒可以走多少米,你不能说它走了米赫兹。
I agree, but I want the speed in meters per second.
我同意,但我希望速度以米每秒为单位
We divide that by the mass, so 0.12 kilograms, that's the mass of a regulation baseball for the major leagues, and the velocity of the baseball is 42 meters per second. So, we can cross out our units doing our unit analysis.
我们用质量来除它,质量为0,12千克,这是大多数联赛规定的棒球质量,棒球的速度为42米每秒,所以,我们可以消去单位,来做单位分析。
Acceleration is measured in meters per second squared.
加速度的单位是米每秒平方
0 of those spikes per second.
每秒钟40次尖峰脉冲。
So, keep in mind that one milliwatt is just the same as saying 1 times 10 to the -3 joules per second.
所以,请记住1毫瓦,和1乘以10的-3次方焦耳每秒,的说法是等同的。
So, if we do this calculation for an electron, saying it moves at 10 to the 5 meters per second, then what we end up with for a wavelength is 7 times 10 to the -9 meters.
如果我们已知电子以,10的5次方每秒的速度运动,那么做一个计算,可以得知它的波长是,7乘以10的负9次方米。
If your plan is to accelerate a 3 kg mass with an acceleration of 2 meters per second, you better have a rope that can furnish that force and it can take the tension of 6 Newtons.
如果你想用 2 米每秒平方的加速度,去拉一个 3 千克的物体,那么你就需要一根能提供拉力的绳子,并且它能够承受 6 牛的张力
Now when it reaches up to the right more towards the heart of that red zone, " 100 spikes per second.
现在,当它移动到,右上侧偏红色区域的时候,我们会听到嗑哩的声音,每秒钟100次,we,may,hear,“keri…
, a 100 spikes per second, ? if me ask you:" where he is planning to reach ?"
因此,当我们听到每秒钟100次,嗑,的声音时,So,if,we,heard,“ke…,如果我问你,人会触摸哪里“
You see an object in motion, you find a and you give a a certain numerical value, 10 meters per second squared.
你看到一个物体在运动,你会发现它的 a,然后给 a 赋值,10 米每秒平方
Frequencies, how many times you go around, f is revolutions per second It's called the angle of velocity.
频率就是一秒转多少圈,因为 f 是每秒转过的圈数,这就是角速度
t look the same to you, because your brain is correctly interpreting them as what once in a shadow, as sending, say a thousand photos per second into my eye.
但是,大家看起来却不一样,But,they,don’,因为你们的大脑正确地给予了解释,处于阴影当中,每秒钟向你的眼睛发出一千张图片。
0 Hertz means you do 60 revolutions per second.
0Hz 的意义是每秒经过60个周期
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