章节大纲

  • A baby crawls and gazes at a chalkboard displaying Einstein's equation E=mc².

    It’s so simple that a baby can understand it! Well, not really, but Einstein’s famous equation is pretty simple: E = mc 2 . Do you know what it means and why it’s so famous?
    ::爱因斯坦的著名方程式很简单:E = mc2. 你知道这意味着什么,为什么它这么出名吗?

    Einstein’s Equation
    ::爱因斯坦的方程式

    Einstein’s equation is possibly the best-known equation of all time.
    ::爱因斯坦的方程式可能是有史以来最著名的方程式。

    There's reason for that. The equation is incredibly important. It changed how scientists view and matter, which are two of the most basic concepts in all of science . The equation shows that energy and matter are two forms of the same thing. This new idea turned science upside down when Einstein introduced it in the early 1900s. Amazingly, the idea has withstood the test of time as more and more evidence has been gathered to support it.
    ::原因就是如此。 等式是极为重要的。 它改变了科学家的观点和物质, 它们是科学中两个最基本的概念。 等式表明, 能源和物质是两种相同的事物。 这个新想法使科学在19世纪初爱因斯坦引入时颠倒了。 令人惊讶的是, 当越来越多的证据被收集来支持它时, 这个想法经受住了时间的考验。

    You can learn more about Einstein's equation in the video below.
    ::您可以在下面的影片中了解更多爱因斯坦的方程式。

    Q : What do the letters in Einstein’s equation stand for?
    ::问:爱因斯坦方程式中的字母代表什么?

    A : E stands for energy, m stands for mass, and c stands for the .
    ::A:E表示能量,m表示质量,c表示能量。

    The speed of light is 300,000 kilometers (186,000 miles) per second, so c 2 is a very big number. Therefore, the amount of energy in even a small mass of matter is tremendous. Suppose, for example, that you have 1 gram of matter. That’s about the mass of a paperclip. Multiplying this mass by c 2 would yield enough energy to power 3,600 homes for a year!
    ::光速是每秒300,000公里(186,000英里),因此C2是一个非常巨大的数字。 因此,即使小物质质量中的能量数量也非常巨大。 比如,假设你拥有1克物质。 这是关于纸板质量的。 用C2乘以这一质量将产生足够能量,使3,600个家庭一年的电力!

    Mass and Energy in Nuclear Reactions
    ::核反应中的质量和能源

    Einstein’s equation helps scientists understand what happens in and why they produce so much energy. When the nucleus of a undergoes fission or fusion in a nuclear reaction, it loses a tiny amount of mass. What happens to the lost mass? It isn’t really lost at all. It is converted to energy. How much energy? E = mc 2 . The change in mass is tiny, but it results in a great deal of energy.
    ::爱因斯坦的等式有助于科学家理解在什么情况下发生,为什么他们生产如此多的能源。 当一个经历的核裂变或核反应中的核聚变的核心失去一小撮质量时,它会失去一小撮质量。 失去的质量会怎样呢? 它并没有真正丧失。 它被转换为能源。 能量有多少? E = mc2 。 质量的变化很小,但是它却导致大量的能量。

    Q : In a nuclear reaction, mass decreases and energy increases. What about the laws of conservation of mass and ? Are mass and energy not conserved in nuclear reactions? Do we need to throw out these laws when it comes to nuclear reactions?
    ::问题:在核反应中,大规模减少和能源增加。 保护质量和? 大规模和能源的法律难道没有在核反应中加以保护吗? 在核反应方面,我们需要废除这些法律吗?

    A : No, the laws still apply. However, it’s more correct to say that the sum of mass and energy is always conserved in a nuclear reaction. Mass changes to energy, but the total amount of mass and energy combined remains the same.
    ::A:不,法律仍然适用。 然而,更正确的是说质量和能源总和总是在核反应中受到保护。 大规模改变能源,但质量和能源总和保持不变。

    Summary
    ::摘要

    • Einstein’s equation, E = mc 2 , shows that matter and energy are two forms of the same thing. It also shows that there is a tremendous amount of energy (E) in a small mass (m) of matter.
      ::爱因斯坦的方程式,E = mc2,表明物质和能源是同一事物的两种形式。 它还表明在小物质质量(m)中有大量能量。
    • In nuclear reactions, matter changes to energy, but the total amount of mass and energy together does not change.
      ::在核反应中,物质对能源的改变,但质量和能源的总量没有变化。

    Review
    ::回顾

    1. Describe in words the meaning of Einstein’s equation, E = mc 2 .
      ::用文字描述爱因斯坦方程式的含义,E=mc2。
    2. Why is this equation so important?
      ::为什么这个方程式这么重要?
    3. How does Einstein’s equation relate to the conservation of mass and energy in nuclear reactions?
      ::爱因斯坦的等式与核反应中保护质量和能源有何关系?