3rd Ed. Lecture-Tutorials For Intro Astronomy: Electromagnetic (EM) Spectrum of Light

Which of the following types of light travels at the fastest speed? Explain.

ALL travel at same constant speed of light

If the Sun were to cool off dramatically and as a result start giving off mainly light at wavelengths longer than visible light, how would the frequency, energy, and speed of light given off by the Sun also be different?

Frequency: lower-longer wavelengths mean shorter frequency Energy: lower frequency means lower energy Speed: same-speed of light is constant

Circle word choice that correctly describes how the two forms of light compare.

Infrared light has [less] energy than ultraviolet light. X-ray photons have [longer] wavelengths than gamma ray photons. Visible electromagnetic radiation has a [higher] frequency than radio wave electromagnetic radiation. Infrared light has [same] speed than microwave light.

Consider the following discussion between two students about the different properties of light.

S1: Disagree. Higher frequency means shorter wavelength. Agree with same speed detail. S2: Disagree. All light travel at constant speed.

Complete following sentence.

The portion of the electromagnetic spectrum of light with the greatest energy has the [highest] frequency and the [shortest] wavelength.

Which of the following has the greatest energy?

Gamma Rays

Which one of the following has the highest frequency?

Gamma Rays

Write a sentence or two that describes how light at the red end of the visible portion of the spectrum and light at the violet end of the visible light portion of the spectrum compare in terms of their energy, frequency, speed, and wavelength.

Light at the red end of the visible portion has the least energy, lowest frequency, same speed, and longer wavelength compared to the violet end.

Which one of the following has the longest wavelength?

Radio Waves