18.9伽马射线
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This amazing image is an artist’s rendition of a gamma ray burst. What is a gamma ray burst? It’s an incredibly energetic explosion that is thought to occur when a massive star collapses. The burst lasts just seconds or minutes, but it has more than a million billion suns! As you might have guessed, gamma rays are released during a gamma ray burst. Gamma rays are extremely energetic .
::这个惊人的图像是艺术家对伽马射线暴的传说。 什么是伽马射线暴?这是一场在巨型恒星崩溃时被认为会发生的异常活跃的爆炸。 爆炸只持续几秒钟或几分钟,但有超过10亿个太阳。 正如你可能猜想的那样,伽马射线在伽马射线暴中被释放。 伽马射线非常活跃。The Range of Electromagnetic Waves
::电磁波的范围Electromagnetic waves transfer energy across space as well as through matter. They vary in their and frequencies, and higher-frequency waves have more energy. The full range of wavelengths of electromagnetic waves, shown in the Figure , is called the .
::电磁波在空间和物质之间转移能量。电磁波的频率和频率各不相同,高频波的能量也更多。图中显示的电磁波波的波长都称为 。What Are Gamma Rays?
::什么是伽马射线?As you can see in the Figure , gamma rays have the shortest wavelengths and highest frequencies of all electromagnetic waves. Their wavelengths are shorter than the diameter of atomic nuclei , and their frequencies are greater than 10 19 hertz (Hz). That’s 10 quadrillion waves per second! Because of their high frequencies, gamma rays are also the most energetic of all electromagnetic waves.
::从图中可以看出,伽马射线具有所有电磁波中最短波长和最高频率。 其波长比原子核直径短,频率大于1019赫兹(赫兹 ) 。 也就是每秒10个四亿波。 伽马射线由于其高频率,也是所有电磁波中最能发力的。Sources of Gamma Rays
::伽马射线源源Gamma rays are given off by radioactive atoms and nuclear explosions. They are also given off by the sun and other stars, as well as by collapsing stars in gamma ray bursts. Fortunately, gamma rays from space are absorbed by Earth’s atmosphere before they can reach the surface.
::伽马射线通过放射性原子和核爆炸而断裂,太阳和其他恒星以及伽马射线暴中恒星的崩溃也使伽马射线断裂。 幸运的是,来自空间的伽马射线在到达地表之前就被地球大气层吸收。Q: Predict how gamma rays might affect living things on Earth if they weren’t absorbed by the atmosphere.
::Q:预测伽马射线如果不被大气吸收,会如何影响地球上的生命。A: Gamma rays would destroy most living things on Earth because they have so much energy.
::A:伽马射线会摧毁地球上大多数生物, 因为它们有如此多的能量。Dangers and Uses of Gamma Rays
::伽马射线的危险和使用The extremely high energy of gamma rays allows them to penetrate just about anything. They can even pass through bones and teeth. This makes gamma rays very dangerous. They can destroy living cells, produce gene mutations, and cause cancer. Ironically, the deadly effects of gamma rays can be used to treat cancer. In this type of treatment, a medical device sends out focused gamma rays that target cancerous cells. The gamma rays kill the cells and destroy the cancer.
::伽马射线极高的能量能让它们渗透到任何东西。它们甚至可以穿透骨头和牙齿。这使得伽马射线非常危险。它们可以摧毁活细胞,产生基因突变,并导致癌症。具有讽刺意味的是,伽马射线的致命影响可以用来治疗癌症。在这种治疗中,医疗装置发出针对癌症细胞的有重点的伽马射线。伽马射线杀死细胞并摧毁癌症。Summary
::摘要-
Electromagnetic waves vary in their wavelengths and frequencies. Higher-frequency waves have more energy.
::电磁波的波长和频率各不相同,高频波的能量更多。 -
Of all electromagnetic waves, gamma rays have the shortest wavelengths and highest frequencies. Because of their very high frequencies, gamma rays have more energy than any other electromagnetic waves.
::在所有电磁波中,伽马射线的波长最短,频率最高,由于频率非常高,伽马射线的能量比任何其他电磁波都大。 -
Sources of gamma rays include radioactive atoms, nuclear explosions, and stars. Gamma rays from space are absorbed by Earth’s atmosphere.
::伽马射线的来源包括放射性原子、核爆炸和恒星,来自空间的伽马射线被地球大气层吸收。 -
Gamma rays can destroy living cells, produce mutations, and cause cancer. They can be used to treat cancer by focusing the deadly rays on cancer cells.
::伽马射线可以摧毁活细胞,产生突变并导致癌症。 它们可以用来治疗癌症,将致命射线集中在癌症细胞上。
Review
::回顾-
What are gamma rays?
::什么是伽马射线? -
Describe the wavelength, frequency, and energy of gamma rays.
::描述伽马射线的波长、频率和能量。 -
What are some sources of gamma rays?
::伽马射线的来源是什么? -
Identify how gamma rays can affect living things.
::确定伽马射线如何影响生命 -
Explain how gamma rays can be used to treat cancer.
::解释伽马射线如何用于治疗癌症。
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Electromagnetic waves vary in their wavelengths and frequencies. Higher-frequency waves have more energy.
