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Astr 1050     Homework 4
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Question 1:   Which of the following are true of electro-magnetic radiation (light)? You can have multiple answers here and must get all of these for full credit (Partial credit is possible).
a.The speed of light within a given medium (e.g., glass) is constant.
b.The speed of light in different mediums (e.g., vacuum vs. air) is different.
c.X-rays penetrate our bodies, but cannot get from space through all the atmosphere down to the ground.
d.Infrared light is absorbed at many wavelengths by water vapor in our atmosphere and has difficulty getting to the ground.
e.Radio waves can have wavelengths of hundreds of meters.
Question 2:   Of the following types of electromagnetic radiation, which has the lowest energy per photon?
a.gamma-rays
b.Radio
c.Infrared radiation
d.Visible
e. X-rays