The following items will test your grasp of the material covered in this lesson. There is only one correct
answer for each item. When you complete the exercise, check your answers with the answer key that
follows. If you answer any item incorrectly, study again that part of the lesson which contains the
Which of the following are primarily used to make long-distance radio transmissions?
Reflected ground waves
The rate at which ionization occurs in the ionosphere depends on the density of atoms in the
atmosphere. What else does it depend on?
The intensity of the infrared light waves
The intensity of the ultraviolet light waves
The intensity of the visible light waves
Which ionospheric layer has the least effect on bending the paths of high frequency radio waves?
Ionospheric reflection generally occurs using which frequencies?