Basic Skills/Definitions Quiz   Chapter 5
Part A
What is the difference between energy and power?
Hint A.1
Study Section 5.1.
ANSWER:

Power is used to describe energy of light, while the term energy has a broader meaning. Power is measured in joules and energy is measured in watts. There's no difference: energy and power are different names for the same thing. Power is the rate at which energy is used, so its units are a unit of energy divided by a unit of time.
Part B
Visible light from a distant star can be spread into a spectrum by using a glass prism or ______.
Hint B.1
Study Section 5.1.
ANSWER:

adaptive optics. a flat glass mirror. a telescope. a diffraction grating.
Part C
Which of the following statements is true of green grass?
Hint C.1
Study Section 5.1.
ANSWER:

It means the lawn is healthy. It transmits all colors of light except green. It absorbs red light and emits green light. It absorbs red light and reflects green light.
Part D
Suppose you watch a leaf bobbing up and down as ripples pass it by in a pond. You notice that it does two full up and down bobs each second. Which statement is true of the ripples on the pond?
Hint D.1
Study Section 5.2.
ANSWER:

They have a frequency of 2 hertz. We can calculate the wavelength of the ripples from their frequency. They have a frequency of 4 hertz. They have a wavelength of two cycles per second.
Part E
Suppose you know the frequency of a photon, and the speed of light. What else about the photon can you determine?
Hint E.1
Study Sections 5.2.
ANSWER:

Its acceleration. Its temperature. The chemical composition of the object that emitted it. Its wavelength and energy.
Part F
When considering light as made up of individual pieces, each characterized by a particular amount of energy, the pieces are called _________.
Hint F.1
Study Section 5.2.
ANSWER:

frequencies wavicles photons gamma rays
Part G
From shortest to longest wavelength, which of the following correctly orders the different categories of electromagnetic radiation?
Hint G.1
Study Figure 5.2.
ANSWER:

Gamma rays, X rays, visible light, ultraviolet, infrared, radio Infrared, visible light, ultraviolet, X rays, gamma rays, radio Gamma rays, X rays, ultraviolet, visible light, infrared, radio Radio, infrared, visible light, ultraviolet, X rays, gamma rays
Part H
If we say that a material is opaque to ultraviolet light, we mean that it _________.
Hint H.1
Study Section 5.1 and 5.2.
ANSWER:

absorbs ultraviolet light Reflects ultraviolet light emits ultraviolet light transmits ultraviolet light
Part I
Suppose you built a scale-model atom in which the nucleus is the size of a tennis ball. About how far would the cloud of electrons extend?
Hint I.1
Study Section 5.3.
ANSWER:

Several kilometers To the Sun A few meters Several centimeters
Part J
Which of the following best describes the fundamental difference between two different chemical elements (such as oxygen and carbon)?
Hint J.1
Study Section 5.3.
ANSWER:

They have different numbers of protons in their nucleus. They have different numbers of electrons. They have different names. They have different atomic mass numbers.
Part K
Consider an atom of carbon in which the nucleus contains 6 protons and 7 neutrons. What is its atomic number and atomic mass number?
Hint K.1
Study Section 5.3
ANSWER:

Atomic number = 13; atomic mass number = 6. Atomic number = 7; atomic mass number = 13. Atomic number = 6; atomic mass number = 13. Atomic number = 6; atomic mass number = 7.
Part L
An atom which has 4 protons and 6 neutrons will be electrically neutral if it contains
Hint L.1
Study Section 5.3.
ANSWER:

4 electrons. 10 electrons. 6 electrons. at least one electron.
Part M
Sublimation is the process in which ___________
Hint M.1
Study section 5.3.
ANSWER:

electrons are stripped from atoms molecules go from the liquid phase to the gas phase. molecules go directly from the solid phase to the gas phase. molecules go from the solid phase to the liquid phase.
Part N
Which of the following transitions is not possible?
Hint N.1
Study Section 5.3
ANSWER:

An electron begins in the ground state and then gains enough energy to become ionized. An electron begins in an excited state and then gains enough energy to become ionized. An electron begins in an excited state and then gains enough energy to jump to the ground state. An electron begins in the ground state and then gains enough energy to jump to an excited state.
Part O
An atom that has fewer electrons than protons is called a/an _________.
Hint O.1
Study Section 5.3.
ANSWER:

ion molecule plasma solid
Part P
Suppose you decide to make a graph of intensity against wavelength for the spectrum shown here. Which of the following shows what the graph will look like?
Hint P.1
Study Section 5.4
ANSWER:


Part Q
Use the figure above to answer questions 1 - 3.Assume the woman in each case uses her prism to look at a spectrum of light coming from the object(s) shown. In which case will she see a continuous rainbow of thermal radiation?
Hint Q.1
Study Section 5.4.
ANSWER:

2 1 3 4
Part R
Assume the woman in each case uses her prism to look at a spectrum of light coming from the object(s) shown. In which case will she see a rainbow of color interrupted by a few dark absorption lines?
Hint R.1
Study Section 5.4.
ANSWER:

2 1 3 4
Part S
Thermal radiation is defined as _________.
Hint S.1
Study Section 5.2.
ANSWER:

radiation that is felt as heat radiation with a spectrum whose shape depends only on the temperature of the emitting object radiation produced by an extremely hot object radiation in the form of emission lines from an object
Part T
According to the laws of thermal radiation, hotter objects emit photons with _________.
Hint T.1
Study Section 5.4.
ANSWER:

a shorter average wavelength a higher average speed a lower average energy a lower average frequency
Part U
Suppose you want to know the chemical composition of a distant star. Which piece of information is most useful to you?
Hint U.1
Study Section 5.4.
ANSWER:

The Doppler shift of the star's spectrum The wavelengths of spectral lines in the star's spectrum The peak energy of the star's thermal radiation Whether the star's spectrum has more emission lines or more absorption lines
Part V
The spectra of most galaxies show redshifts. This means that their spectral lines _________.
Hint V.1
Study Section 5.4.
ANSWER:

have wavelengths that are longer than normal have wavelengths that are shorter than normal have a higher intensity in the red part of the spectrum always are in the red part of the visible spectrum
Part W
You observe a distant galaxy. You find that a spectral line, resulting from an electron transition in hydrogen, is shifted from its normal location in the visible part of the spectrum into the infrared part of the spectrum. What can you conclude?
Hint W.1
Study Section 5.5.
ANSWER:

The galaxy has very weak gravity. The galaxy is made purely of hydrogen. The galaxy is moving towards you.