Download Light and Spectroscopy Concept Inventory

Light and Spectroscopy Concept Inventory
Instructions:
Indicate the best answer for each question on the separate answer sheet.
There are 28 questions in total.
PLEASE DO NOT WRITE ON THIS PAPER.
USE THE SEPARATE ANSWER SHEET.
READ ALL QUESTIONS CAREFULLY.
PLEASE RETURN THE INVENTORY TO YOUR INSTRUCTOR
ALONG WITH YOUR COMPLETED ANSWER SHEET.
**BE SURE TO PROVIDE ONLY YOUR STUDENT ID # (AS ISSUED BY YOUR
COLLEGE OR UNIVERSITY) IN THE DESIGNATED AREA OF YOUR ANSWER
SHEET.**
LSCI Spring 2006
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Light and Spectroscopy Concept Inventory
1. Which of the following travels slowest through space?
a. Radio waves.
b. Visible light.
c. X-rays.
d. Infrared photons.
e. They all travel at the same speed.
2. Consider the dark line absorption spectra shown below for Star X and Star Z. What can you
determine about the colors of the two stars? Assume that the left end of each spectrum
corresponds to shorter wavelengths (blue light) and that the right end of each spectrum
corresponds with longer wavelengths (red light).
Star X
a.
b.
c.
d.
Star Z
Star X would appear blue and Star Z would appear red.
Star X would appear red and Star Z would appear blue.
Both stars would appear the same color.
The colors of the stars cannot be determined from this information.
3. Consider the 3 stars described below.
• Star X gives off the same amount of energy as the Sun and gives off most of its energy
at a wavelength of 400 nm.
• Star Y gives off more energy than the Sun and gives off most of its energy
at a wavelength of 800 nm.
• Star Z gives off less energy than the Sun and gives off most of its energy
at a wavelength of 600 nm.
Which star is the coolest?
a. Star X.
b. Star Y.
c. Star Z.
d. The relative temperatures of these stars cannot be determined from this information.
4. Which of the following causes starlight to be redshifted?
a. A temperature change in the star.
b. Dust between the observer and the star.
c. Motion of the star.
d. Aging of the star.
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5. A photon of which color of light carries the most energy?
a. Red.
b. Yellow.
c. Green.
d. Blue.
e. All photons have the same energy.
6. Use the Luminosity vs. Temperature graph to determine the correct ranking for the sizes
(diameters) of the 3 stars H, J, and K from LARGEST to SMALLEST.
Bright
a.
b.
c.
d.
e.
H=J>K
H>J>K
J>H>K
J>K>H
K=J>H
J
H
Luminosity
K
Dim
Hot
Cool
Temperature
Use the drawings below to answer the next two questions.
A.
B.
e-
C.
e-
D.
e-
e-
7. Which drawing (not to scale) represents the process by which an absorption line is formed?
a. A.
b. B.
c. C.
d. D.
8. Which drawing (not to scale) represents the process by which an emission line is formed?
a. A.
b. B.
c. C.
d. D.
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Energy Output per second
A
VIBGYOR
a.
b.
c.
d.
e.
Wavelength
B
VIBGYOR
C
Energy Output per second
Energy Output per second
9. The three spectral curves shown in the graphs below illustrate the energy output versus
wavelength for three unknown objects A, B, and C. Which of the objects has the highest
temperature?
Wavelength
VIBGYOR
Wavelength
A.
B.
C.
All three objects have the same temperature.
The relative temperatures of these objects cannot be determined from this
information.
10. Which of the following has the shortest wavelength?
a. A photon of ultraviolet light.
b. Blue electromagnetic radiation.
c. An X-ray.
d. A radio wave.
e. Infrared radiation.
11. Imagine that you are observing the Sun while in a space ship far above the Earth’s
atmosphere. Which of the following spectra would you observe by analyzing the sunlight?
a. Dark line absorption.
b. Bright line emission.
c. Continuous.
12. Which of the two objects (A or D) is at a higher temperature?
a. Object A.
b. Object D.
c. The two objects have the same temperature.
d. It is not possible to infer this relationship from the graph.
D
A
Energy Output per second
Use the graph at the right to answer the next question.
Wavelength
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13. Energy is released from an atom in the form of light when electrons:
a. are emitted by the atom.
b. move from low energy levels to high energy levels.
c. move from high energy levels to low energy levels.
d. move in their orbit around the nucleus.
The following diagram represents three electromagnetic waves emitted simultaneously by the
Sun. Use this diagram for the next 2 questions.
Wave 1
Wave 2
Wave 3
14. Which wave represents electromagnetic radiation with the highest energy?
a. Wave 1.
b. Wave 2.
c. Wave 3.
d. All three waves have the same amount of energy.
15. Which wave will arrive first at a satellite orbiting just above the Earth’s atmosphere?
a. Wave 1.
b. Wave 2.
c. Wave 3.
d. All three waves will arrive simultaneously.
16. Star E and Star T give off the same amount of energy, but Star E is hotter than Star T. How
does the surface area of E compare to the surface area of T?
a. E has a larger surface area than T.
b. E has a smaller surface area than T.
c. E and T have the same surface area.
d. There is insufficient information to answer this question.
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17. The bright line emission spectrum shown above is characteristic of the region of the nebula
marked in the drawing. By comparing the positions of the lines in the spectrum to a known
laboratory spectrum on Earth, which of the following properties of the nebula can be directly
determined?
a. Motion towards or away from Earth only.
b. Temperature only.
c. Chemical composition (type of atoms) only.
d. Motion and chemical composition.
e. Motion, temperature, and chemical composition.
Use the four spectra shown to the right for objects A-D, to answer the next two questions. Note
that one of the spectra is from an object at rest (not moving) and the remaining spectra
come from objects that are all moving toward the observer. Assume that the left end of each
spectrum corresponds to shorter wavelengths (blue light) and that the right end of each spectrum
corresponds with longer wavelengths (red light).
18. Which of the four objects A-D is at rest?
a. Object A.
b. Object B.
c. Object C.
d. Object D.
19. Of the three objects that are moving, which is
moving with the slowest speed?
a. Object A.
b. Object B.
c. Object C.
d. Object D.
e. They are all moving the same speed, the
speed of light.
LSCI Spring 2006
Object A
Object B
Object C
Object D
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20. The coolest stars emit most of their energy in which portion of the electromagnetic spectrum?
a. X-ray.
b. Infrared.
c. Visible.
d. Ultraviolet.
21. If the light coming from a distant object produces a bright line emission spectrum, what kind
of object is it?
a. Hot and dense.
b. Cool and dense.
c. Hot and diffuse.
d. Cool and diffuse.
22. Shown below are the spectra of stars P and Q. How does the temperature of the two stars
compare? Assume that the left end of each spectrum corresponds to shorter wavelengths
(blue light) and that the right end of each spectrum corresponds with longer wavelengths
(red light).
Star P
Star Q
a.
b.
c.
d.
Star P is at the higher temperature.
Star Q is at the higher temperature.
Both stars are the same temperature.
The relative temperatures of the stars cannot be determined from this information.
23. Which of the following is true about comparing visible light and radio waves?
a. The radio waves have a lower energy and travel slower than visible light.
b. The visible light has a shorter wavelength and a lower energy than radio waves.
c. The radio waves have a shorter wavelength and higher energy than visible light.
d. The visible light has a higher energy and travels faster than radio waves.
e. The radio waves have a longer wavelength and travel the same speed as visible light.
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Use the spectral curves for objects A-D shown below to answer the next three questions. The
scale is the same for all four graphs.
visible
range
Object A
VIBGYOR
Energy Output per second
Energy Output per second
visible
range
Wavelength
VIBGYOR
Wavelength
visible
range
Object C
Wavelength
Energy Output per second
Energy Output per second
visible
range
VIBGYOR
Object B
Object D
VIBGYOR
Wavelength
24. Which, if any, of the other objects has the same temperature as object B?
a. Object A.
b. Object C.
c. Object D.
d. They are all the same temperature.
e. There is insufficient information to answer this question.
25. Which, if any, of the objects could be approximately the same size as object D?
a. Object A.
b. Object B.
c. Object C.
d. They could all be the same size.
e. None of the above.
26. Which of these objects is the smallest?
a. Object A.
b. Object B.
c. Object C.
d. Object D.
e. More than one of these objects is the smallest.
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27. What is your gender?
a. Female
b. Male
28.
Have you previously taken an astronomy course? (Do NOT count this course in your
response.)
a. Yes
b. No
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