与标准方法乘以十进制

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CK-12 Interactive Widget
::CK-12 交互式部件

 

 

 

 

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How much force does a toy car exert?
::玩具车能施多少力?

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You can measure the force that something exerts in Newtons.
::你可以量量牛顿的威力 牛顿的威力

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• The force of an apple falling off a tree  is 1 Newton.
  ::苹果从树上掉下来的威力是1牛顿
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• T he force of a human bite is 720 Newtons.
  ::人类咬伤的威力是720牛顿
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• T he force of a Great White Shark bite is 18,000 Newtons.
  ::大白鲨咬的威力是18000牛顿
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• T he force of a small car at peak acceleration is 45,000 Newtons.
  ::一辆小汽车在高峰加速度时的威力是45 000牛顿。
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• The force of the thrust of a space shuttle main engine at liftoff is 1,800,000 Newtons.
  ::航天飞机主引擎在起飞时的推力是1800 000牛顿。

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You can see the weight of each car in pounds in the interactive.  In order to find the Newtons for each car, convert the weight to kilograms by multiplying by 0.454 kilograms/pound then multiply by 10 meters per second². 
::您可以在互动中看到每辆车的重量。 为了找到每辆车的牛顿, 将重量转换成公斤, 每公斤乘以0. 454公斤, 然后乘以每秒10米。

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To learn more about force and Newtons, take a look at this .
::更多了解力和牛顿, 看看这个。

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In the interactive below, find the remote control car that exerts the most force by multiplying the decimal kilogram (kg) values with the car's acceleration ( $\begin{align*}\frac{m}{s^2}\end{align*}$ ).
::在下文互动中,通过乘以小数千克值和汽车加速度(ms2),发现遥控车的威力最大。

 

 

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 In Physics, force is defined as a push or pull acting on an object.  Force is measured in Newtons.  Force can be found using this equation:
::在物理中, 力被定义为对对象的推力或拉力动作。 力在牛顿中测量。 力可以使用此方程式找到 :

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$\begin{align*}F=m\times a\end{align*}$  
::F=mxa

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$\begin{align*}F\end{align*}$   represents the force in Newtons (N) ,  $\begin{align*}m\end{align*}$  represents mass measured in kilograms (kg), and  $\begin{align*}a\end{align*}$  represents acceleration as meters divided by seconds squared $\begin{align*}\left(\tfrac{\textrm{m}}{{\textrm{s}}^{2}}\right).\end{align*}$

::F代表牛顿(N)的力量,m代表以公斤(kg)测量的质量,m代表加速度,以米除以秒平方(ms2)。

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$\begin{align*}1 \ \textrm{N} = 1 \ \textrm{kg} \cdot 1 \ \frac{\textrm{m}}{{\textrm{s}}^{2}}\end{align*}$  
::1 N=1千克=1毫升2

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Because the  mass of the cars are given in pounds, you have to convert the  pounds to kilograms before finding the force.
::因为汽车质量是按磅计的, 你必须先把磅转换成公斤才能找到力量。

 

 

 

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How much does it cost to fill a mini bike with gas?
::用煤气填满一辆迷你自行车要花多少钱?

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Rachel has a motorized mini bike with a fuel tank that holds 0.32 gallons. The cost of gas in her neighborhood is $2.859 per gallon.
::Rachel有一辆机动小型自行车,油箱装有0.32加仑的燃料,附近汽油的成本是每加仑2.859美元。

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Use the interactive to see how much it costs to fill Rachel's mini bike with gas by solving the expression below.
::使用互动来查看瑞秋迷你车的汽油装填成本, 解决下面的表达方式。

 

 

 

 

 

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How do you calculate the  focus  of a microscope?
::您如何计算显微镜的焦点 ?

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Microscopes zoom in  to magnify something small and make it easier to see.  To  show a small  object very clearly, microscopes get very close to the object and use stuff that magnifies the image like water, glycerin or oil. 
::显微镜放大到放大小物体, 使其更容易看到。 要非常清楚地显示一个小物体, 显微镜会非常接近物体, 并使用放大图像的东西, 如水、 甘油或油 。

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In the interactive below, notice how the numbers increase or decrease as you change the zoom and the stuff between the lens and the glass. Use the numbers to help you answer the questions that follow.
::在下面的交互式互动中,请注意当您改变镜头和玻璃之间的缩放和物质时数字的增减。使用数字来帮助您回答接下来的问题。

 

 

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Scientists use Numerical Aperture to measure the clarity of the  zoom under a microscope. To find the Numerical Aperture, multiply numbers from the interactive .
::科学家使用数字孔径测量显微镜下缩放的清晰度。要找到数字孔径,请从互动中乘以数字。

 

 

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To learn more about microscopes, you can use this .
::要更多了解显微镜, 您可以使用这个 。

Summary

播放段落 Remember when multiplying decimals, don’t line them up by the decimal point. Line them up by the last digit on the right. ::记住当乘以十进制时, 不要在小数点前排队。 请在右侧最后一位数前排队 。 播放段落 When placing the decimal point, look at the total number of digits to the right of the decimal and space the decimal point that many places to the left. ::键入小数点时,请查看小数点右侧的数字总数,小数点在左方很多位的位数为小数点的间距。