From what you have stated, it is obvious that you are confused with Velocity and acceleration.
E = 1/2 mass * velocity * velocity which is the formula you have been using. It has nothing to do with Acceleration.
自动车加速上坡， 油门是一直踩着，还是松一松再踩？
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From what you have stated, it is obvious that you are confused with Velocity and acceleration.
E = 1/2 mass * velocity * velocity which is the formula you have been using. It has nothing to do with Acceleration.
I have already stated, "Acceleration depends on both HP(KW) and Torque(N*M). In order for a car to accelerate fast, you will need enough torque to overcome friction, the greater the force is, the fast the acceleration is(F = ma). However, because the way transmission gears are designed when connected to engine with flywheel, lower gears providing more force, higher gear providing more speed. You will have to find the balance in between. "
mianfei
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在变功率，变扭矩条件下，计算能量，用功率对时间积分一目了然，有些蠢人非要用扭矩变换到驱动力，然后与速度来积分，结果连自己都搞不清楚怎么回事了，告诉你个办法，做个积分变换，结果就是一样。用扭矩不是不能算，关键你有没有那个理解能力，一个积分变换后两者是一样的，但那个更容易使显而易见的，没那金刚钻就别拦子瓷器活儿。
一直用最大功率做功与功率时低时高（不高于最大功率），给定时间内，那个做的总功最多，只要不是傻子都能一眼瞧懂。
如果确实有智力缺陷的话，换个例子，对各水池注水，大管子出水速度慢，小管子出水速度快，哪个最先注满水池？你可以在大小，快慢上纠缠不清，也可以简单比较一下单位时间出水量的差异，结果一幕了然。如果两个管子单位时间出水量最大一样，一个一直用最大出水量来灌水，另一个时快时慢，那个效率高？这也是一个幼儿园级别的问题吧？
人不好好学数学的话，使很容易变蠢的。
一直用最大功率做功与功率时低时高（不高于最大功率），给定时间内，那个做的总功最多，只要不是傻子都能一眼瞧懂。
如果确实有智力缺陷的话，换个例子，对各水池注水，大管子出水速度慢，小管子出水速度快，哪个最先注满水池？你可以在大小，快慢上纠缠不清，也可以简单比较一下单位时间出水量的差异，结果一幕了然。如果两个管子单位时间出水量最大一样，一个一直用最大出水量来灌水，另一个时快时慢，那个效率高？这也是一个幼儿园级别的问题吧？
人不好好学数学的话，使很容易变蠢的。
Simply explain "F = mass * acceleration" to me. Where is your power(watt) in that equation?
Do you even know what is acceleration. Acceleration = Force / mass (in this case, time is irrelevant).
I don't see any reason to use Time, Watt and Joule in here.
Do you even realize that we are talking about Acceleration, we have not conclude final distance traveled - which is work done in this case. We are talking about Acceleration at certain point.
Do you even know what is Torque and how does Torque applies to car? Do you even know what is Angular velocity and how it applies to car?
BTW, you seems to like to provoke people by insulting people when you can't prove a point.
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我不是你的物理或数学老师，没有义务辅导这些简单问题。Acceleration = Force / mass没错，但是发动机的输出力与车轮的输出驱动力不是一回事，因为有变速箱！用力来算时，需要使用的是车轮的驱动力，而不是发动机的输出力，不是是个力就可以拿来用的，还好你没有使用你转方向盘的胳膊出的力，低档比较高档条件下，发动机要多转很多圈，轮子转同样快，说你理解不了变速箱，你还不信：理想变速箱中恒定的是扭矩而不是力，真相搞明白的话，基于这样的智力水平就别玩这个花样，从发动机的扭矩来然后加上变速处理来算了，老老实实将整个车当作一个黑盒子，用功率对时间积分少了这个弯，还简单一些，功率一直最大时就是功率乘以时间等于功，这连计算和公式都不需要，因为这是功率的定义： 做功的“快慢“叫功率。更何况4冲程汽油机的最大扭矩只发生在做功冲程的很小的一段时间内，而不是一个恒定值。
这个简单的道理竟然扯了折磨就，我到此打住了。你随便说吧，骂我蠢也随便，我从不介意，因为只要两种人会这么干，第一种是蠢人，第二种是逼我聪明的人，第一种没什么好理会的，第二种人我服气。毕竟在这个国家评价智力基本是合法的，之所以说基本，因为不可以歧视智障人士（比如阻止就业，提供服务等），但可以说出智障这个事实。
这个简单的道理竟然扯了折磨就，我到此打住了。你随便说吧，骂我蠢也随便，我从不介意，因为只要两种人会这么干，第一种是蠢人，第二种是逼我聪明的人，第一种没什么好理会的，第二种人我服气。毕竟在这个国家评价智力基本是合法的，之所以说基本，因为不可以歧视智障人士（比如阻止就业，提供服务等），但可以说出智障这个事实。
1. You are the one who started with all "一种智商上的优越感油然而生" and "有些蠢人非要用扭矩变换到驱动力" which is why I sent you a QQH "If you like to discuss, we can discuss. If you like to provoke or call people stupid, I can do that too. " and tried to ask you to do a discussion more politely and you are now blaming me calling you stupid.
2. You have stated "发动机的输出力与车轮的输出驱动力不是一回事，因为有变速箱！" which is what I have stated Torque is involved. Torque is the moment of force which is the tendency of force to rotate a object through axle. If you want to invent a formula and calculate Acceleration by using Watt, go ahead please. I will be glad to see it.
3. You have stated "低档比较高档条件下，发动机要多转很多圈，轮子转同样快，说你理解不了变速箱，你还不信" which I have explained earlier "Engine speed commonly known as RPM is not equal to Transmission Speed(when engine running at same RPM, gears in transmission might run at different speed".
4. You have stated "理想变速箱中恒定的是扭矩而不是力，同等扭矩下档越低，变速箱输出的力越小" Torque output from transmission is transferred to wheel directly (for the sake of argument, front wheel drive car nothing between wheel and tranny). Due to Torque is the moment of force or tendency of force to rotate a object, in the case of car, it's commonly used to as the force to calculate acceleration. "
5. "我不是你的物理或数学老师，没有义务辅导这些简单问题。Acceleration = Force / mass" A lot of people like to find excuse when they can't answer others' question.
6. "基于这样的智力水平就别玩这个花样" which clearly indicate that you are trying to insult people and I would like to say the similar thing to you now "基于这样的知识水平就别玩这个花样".
You have been say the same thing, but with no formula or anything to prove your point. I have been doing a discussion, but you have been insulting people. It's a free country, you can say anything you want, but respect is much appreciated.
BTW. Why would people will use lower gear to go up hill or when using automatic transmission with cruise control, you tranny will down shift to maintain your speed - which is directly related to the original topic.
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读到一个Volvo Car Driving Manual， 关于LZ 自动车加速上坡， 油门是一直踩着，还是松一松再踩？ 看来是有用的。
Kickdown
http://new.volvocars.com/ownersdocs/2003/2003_s80/03s80_06a.htm#pg74
Automatic shift to a lower gear (kickdown) is achieved by depressing the accelerator pedal fully and briskly. An upshift will occur when approaching the top speed for a particular gear or by releasing the accelerator pedal slightly. Kickdown can be used for maximum acceleration or when passing at highway speeds.
Kickdown
http://new.volvocars.com/ownersdocs/2003/2003_s80/03s80_06a.htm#pg74
Automatic shift to a lower gear (kickdown) is achieved by depressing the accelerator pedal fully and briskly. An upshift will occur when approaching the top speed for a particular gear or by releasing the accelerator pedal slightly. Kickdown can be used for maximum acceleration or when passing at highway speeds.
