动能能

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Have you ever watched a cat in action? 
::你看过猫在行动吗?

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When cats are chasing something, they move very fast. We may comment, “That cat has a lot of energy”. In saying that, we are more correct than we realize. One form of energy is seen when an object is moving and this type of energy is the basis for many chemical processes.
::当猫在追寻某种东西时,它们动作非常快。 我们可以评论 , “ 这只猫有很多能量 ” 。 说到这一点,我们比我们意识到的更正确。 当一个物体在移动,这种能量是许多化学过程的基础时,一种能量的形式就会显现出来。

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SI Kinetic Energy Units
::光生动能单位

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An object’s kinetic energy is the energy due to motion. Kinetic energy can be defined mathematically as
::物体的动动能能量是运动产生的能量。

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$$\begin{align*}\text{KE} = \frac{1}{2} \ \text{mv}^2\end{align*}$$
::KE=12 mv2

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where $\begin{align*}\text{KE} = \text{kinetic energy}\end{align*}$
::KE = 动能

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$\begin{align*}\text{m} = \text{mass}\end{align*}$
::m=质量

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$\begin{align*}\text{v} = \text{velocity}\end{align*}$
::v=速度

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Energy is defined as the capacity to do work or to produce . As discussed previously, kinetic energy is one type of energy and is associated with motion. Another frequently encountered energy is potential energy , a type of energy that is stored in matter and released during a . The joule (J) is the SI unit of energy and is named after English physicist James Prescott Joule (1818-1889). If we go back to the equation for kinetic energy written above, we can put units in (kg for mass and m ² /s ² for velocity squared). Then, in terms of a joule is equal to a kilogram times meter squared divided by a second squared (kg • m ² /s ² ). Another common unit of energy that is often used is the calorie (cal), which is equivalent to 4.184 J.
::能源的定义是工作或生产的能力。如前所述,动能是一种能源,与运动有关。另一个经常遇到的能源是潜在的能源,一种储存在物质中的能源,在物质中释放出来。焦耳(J)是SI的能源单位,以英国物理学家詹姆斯·普莱斯科特·朱莱命名(1818-1889年)。如果我们回到上面写成的动能方程式,我们可以放入单位(质量公斤和速度正方形的m2/s2)。然后,以焦耳为单位,等于一公斤乘以第二平方(千克/m2/s2)。 通常使用的另一个常见能源单位是热量(卡),相当于4.184焦耳。

 

 

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Summary
::摘要

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• Energy is the capacity to do work or to produce heat.
  ::能源是工作或生产热能的能力。
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• Kinetic energy is the energy due to motion.
  ::动能是运动的能量
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• Potential energy is energy stored in matter.
  ::潜在能源是储存在物质中的能源。
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• The joule (J) is the SI unit of energy and equals kg • m ² /s ² .
  ::焦耳(J)是SI的能量单位,等于公斤/平方米2。

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Review
::回顾

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1. What is kinetic energy?
   ::什么是动能?
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2. What is the mathematical equation for kinetic energy?
   ::动能的数学公式是什么?
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3. What is potential energy?
   ::什么是潜在的能源?
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4. What is the SI unit for energy?
   ::什么是SI单位的能源?