Question

You view a visible light spectrum from an unknown object. You see a rainbow with many thin black lines missing. What sort of spectrum is this and what does it tell you?

a) Emission spectrum, indicating a hot, dense object
b) Absorption spectrum, indicating a cooler object in front of a hot background
c) Continuous spectrum, indicating a solid object
d) Blackbody spectrum, indicating a perfect radiator

Answer 1

An absorption spectrum is observed when there are many thin black lines missing from the visible light spectrum, indicating a cooler gas that absorbs certain wavelengths of light in front of a hot background.

Step-by-step explanation:

When you see a visible light spectrum with many thin black lines missing, you are looking at an absorption spectrum. This kind of spectrum indicates the presence of a cooler gas in front of a hotter, light-emitting background.

The black lines, or missing parts of the rainbow, correspond to wavelengths of light that are absorbed by the gas. The unique pattern of these lines can tell us about the composition of the gas that is absorbing light. In contrast, an emission spectrum would show only specific bright lines representing the wavelengths of light emitted by the gas, while a continuous spectrum would display an uninterrupted range of colors.