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Is light composed of particles or waves?
光是由粒子组成的还是波组成的？
Atomic electrons have specific allowed energy
states. Why?
原子电子具有特定的允许能级。为什么？
If atoms occupy only certain allowed levels, how
do they get from one allowed level to another?
如果原子只能占据特定的能级，它们如何从一个能级跃迁到另一个能级？
Why do atoms emit or absorb only certain specific
colors of light?
为什么原子只能发射或吸收特定颜色的光？
How can you tell that there is calcium in the atmosphere
of the star Betelgeuse, which is about 310 light years
away from the earth?
如何判断参宿四星大气中有钙存在？该星距离地球约310光年。
Why is it that you are transparent to radio waves,
more and more opaque as the frequency increases
to the visible and ultraviolet part of the spectrum,
and then suddenly transparent again when you get
to the xray part of the electromagnetic spectrum?
为什么你对无线电波是透明的，随着频率增加到可见光和紫外部分，你变得越来越不透明，而在到达电磁波谱的X射线部分时，你又突然变得透明？
Why do you say that ultraviolet exposure might involve
some risk of skin cancer, whereas exposure from your
microwave oven carries no such risk?
为什么你说紫外线暴露可能涉及皮肤癌的风险，而微波炉的暴露则没有这样的风险？
What types of radiation make up the ionizing radiation
which we might be exposed to?
我们可能暴露于哪种类型的辐射？
What is a laser?
什么是激光？
What are the characteristic properties which make
the light from a laser unique?
什么是使激光光独特的特点？
What is a hologram? What properties distinguish a
hologram from an ordinary photograph?
什么是全息图？哪些特性使全息图区别于普通照片？
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