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Flashcards in Chapter 4 Deck (15)
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1

Wien's law states that the wavelength of the peak radiation emitted by a blackbody is ________ the temperature of a blackbody.

inversely proportional to

2

Stefan's law states that the total energy radiated by a blackbody depends on the ________ power of the temperature of the blackbody.

fourth

3

Imagine an emission spectrum produced by a container of hydrogen gas. Changing the amount of hydrogen in the container will change the colors of the lines in the spectrum.

False

4

Imagine an emission spectrum produced by a container of hydrogen gas. Changing the gas in the container from hydrogen to helium will change the colors of the lines occurring in the spectrum.

True

5

An electron moves to a higher energy level in an atom after absorbing a photon of a specific energy.

True

6

A star much cooler than the Sun would appear

red.

7

Astronomers analyze starlight to determine a star's

1. motion.
2. temperature.
3. composition.

8

According to Figure 2.11 in the textbook (Blackbody Curves), an object having a temperature of 1000 emits mostly

infrared light

9

The effect of a cool, dilute gas between an observer and a continuous hot source is that ________.

dark absorption lines will appear in the spectrum. The cool gas will absorb light from the source only at certain specific wavelengths, producing absorption lines.

10

What kind of spectrum does the Sun have?

An absorption spectrum.

11

Which of the following photons is most energetic?

Gamma-ray

12

In non-ionized hydrogen, for instance, what does a higher orbital state have more of than a lower orbital state?

Energy

13

Which of the following statements does NOT apply to the structure of atoms?

Protons and electrons make up the nucleus. there are no electrons in the nucleus.

14

When an electron goes from a higher energy level back down to the ground state, what is the most accurate way to describe the light it emits?

One or more photons, equal in total energy to the energy the electron absorbed to move up to the higher level. The higher the initial "jump" the more possibilities for the number of photons emitted. However, the total energy must always be the same as the energy originally absorbed.

15

What will happen to the absorption and/or emission spectral lines of an object moving away from Earth at high speed?

They will be shifted toward the red end of the spectrum. Redshift always results when the source and observer are moving away from each other.