Astronomy1: Midterm 3 Practice Exam
True/False (+2 points each)
Indicate whether the sentence or statement is true or false. On your scantron mark A for true and B for false.
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1. Once an object reaches inside the event horizon of a black hole, it can only escape its gravitational pull if it
travels at the speed of light.
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2. Blue light has more energy than red light.
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3. Light is both a particle and a wave.
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4. When the temperature of an object increases, the peak wavelength it emits decreases.
Multiple Choice (+2 points each)
Identify the letter of the choice that best completes the statement or answers the question.
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5. Who discovered Pluto?
a. William Herschel
b. Edwin Hubble
c. Clyde Tombaugh
d. Galileo Galilei
6. Which of the following forms of radiation has the highest energy and is completely blocked by the Earth’s
atmosphere?
a. radio
b. ultra-violet
c. gamma rays
d. visible light
e. microwave
7. Who was the first to develop a system to classify stars based upon their spectral types?
a. Isaac Newton
b. Helen Keller
c. Annie Cannon
d. Albert Einstein
e. Galileo Galilei
8. Which of the following color of stars is the hottest?
a. red
b. blue
c. yellow
d. orange
9. The term that best describes all the possible forms/ wavelengths of light that can exist is called:
a. the electromagnetic spectrum.
b. the visible spectrum.
c. the photo-electric spectrum.
d. the rainbow specrum.
10. What percentage of the mass of our Solar System is the Sun?
a. 49.95%
b. 99.85%
c. 70.57%
d. 25.45%
____ 11. Who was the first to prove that white light is the sum of all wavelengths?
a. Albert Einstein
b. Isaac Newton
c. Annie Cannon
d. Galileo Galilei
____ 12. Who was the first to observe sunspots?
a. Annie Cannon
b. Albert Einstein
c. Galileo Galilei
d. Isaac Newton
____ 13. What is the approximate lifetime of our Sun?
a. 5 billion years
b. 10 billion years
c. 50 billion years
d. 100 million years
____ 14. What type of radiation does our Sun mostly produce?
a. ultraviolet
b. infrared
c. radio
d. gamma rays
e. white light
____ 15. In the nuclear fusion of hydrogen, when 4 hydrogen atoms combine, they form
a. oxygen
b. carbon
c. iron
d. helium
____ 16. How many moons does Pluto have?
a. 3
b. 4
c. 2
d. 5
e. 1
____ 17. Which type of radiation do humans and objects cooler than the stars mostly emit?
a. ultraviolet
b. x-ray
c. visible
d. infrared
e. gamma rays
____ 18. What kind of spectrum do stars mostly emit?
a. continuous spectrum
b. absorption line spectrum
c. emission line spectrum
d. high density spectrum
Completion (+1pt)
Complete each sentence or statement.
19. What type of object is Pluto now according to the IAU? _______________________
Short Answer (+2 pts)
20. Describe in detail what causes meteor showers to occur on the Earth.
21. Describe Einstein’s general theory of relativity and how it explains why gravity works.
22. Describe or carefully draw what is meant by the wavelength of light.
Short Answer (+3 points each)
23. Describe in detail two methods that Astronomers use to detect black holes.
24. Describe specifically the best reason why Pluto is no longer a planet? In your description, include the three
criteria that an object must fulfill in order to be considered a planet.
25. a) Why are sunspots dark? b) What causes sunspots to occur? c) How long does the sunspot cycle last?
Essay (+6 pts)
26. Choose only 1 to answer: a) What will happen to a low mass star like our Sun after it uses up all its
hydrogen in the core? (to earn full credit, you need to describe the properties of and name the old age and
elderly stage of the star) OR b) What will happen to high mass stars after it uses up all its hydrogen in the
core?(to earn full credit, you need to describe the properties of and name the old age and elderly stage of the
star.