No Notes, No Books; You Can Use Calculators s3

Astronomy 101, Exam #2 Review

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No notes, No books; You can use calculators c = 3 x 108 m/s 1 AU = 1.49 ×1011 meters 1 light year = 9.46 × 1015 meters

-34 24 30 h = 6.626 x 10 J●s mass of Earth = 5.97 × 10 kg mass of Sun = 1.99 x 10 kg G = 6.67 × 10-11 m3 kg-1 s-2 mass of Moon = 7.35 x 1022 kg mass of Jupiter = 1.90 x 1027 kg g = 9.8 m/s2 radius of Earth = 6.38 × 106 m radius of Jupiter = 7.15 × 107 m σ = 5.67 x 10-8 W m-2 K-4 1 nm = 1 x 10-9 meters radius of Moon = 1.74 × 106 m

1) Why were the first images from the Hubble Space Telescope blurry?

A) The gyroscopes were faulty. B) The mirror was too flat at the edges. C) The lenses were too thick. D) The telescope was too hot. E) The telescope was too heavy.

2) If it is 400o Celsius, what is the temperature in Kelvin?

A) 27.15 Kelvin B) 136.85 Kelvin C) 573.15 Kelvin D) 883.15 Kelvin E) 673.15 Kelvin

3) From a measurement in the laboratory, we know that a particular spectral line formed by hydrogen appears at a wavelength of 486.1 nm. The spectrum of a particular star shows the same hydrogen line appearing at a wavelength of 485.7 nm. What can we conclude from this observation?

A) The star is getting hotter. B) The star must be very distant. C) The star is getting colder. D) The star is moving away from us. E) The star is moving toward us. Astronomy 101, Exam #2 Review

4) An infrared photon has a frequency of 1 x 1013 Hz. What is the wavelength of this photon?

A) 3 x 10-5 meters B) 6.626 x 10-21 meters C) 3 x 108 meters D) 6.626 x 10-6 meters E) 3 x 1021 meters

5) As the wavelengths of photons of light increase, their …

A) Frequencies increase and their energies increase B) Frequencies decrease and their energies increase C) Frequencies decrease and their energies decrease D) Frequencies increase and their energies stay the same E) Frequencies stay the same and their energies stay the same

6) Which of the following objects has the most kinetic energy?

A) A 10 kg mass moving at 1 km/s. B) A 2 kg mass moving at 2 km/s. C) A 2 kg mass moving at 5 km/s. D) A 5 kg mass moving at 2 km/s. E) A 3 kg mass moving at 3 km/s.

7) Why was the newly discovered ring around Saturn discovered with a satellite that could measure infrared light and not with a satellite that could measure visible light?

A) no satellites that could measure visible light are currently in space B) the particles in the rings are so cold that they are brighter in the infrared than in the visible C) visible light can’t penetrate the Earth’s atmosphere D) visible light can’t travel through dust E) infrared light has a much longer frequency than visible light so it is easier to detect in space Astronomy 101, Exam #2 Review

8) You heat a black ball from a temperature of 400 Kelvin to a temperature of 800 Kelvin. Which of these statements is true?

A) Twice as much energy per second is emitted by the hotter body. B) Four times as much energy per second is emitted by the hotter body. C) Eight times as much energy per second is emitted by the hotter body. D) Sixteen times as much energy per second is emitted by the hotter body. E) Three hundred times as much energy per second is emitted by the hotter body.

9) The nucleus of an atom may contain …

A) neutrons and electrons. B) protons and neutrons. C) ions. D) protons and electrons. E) neutrinos and electrons

10) What is the frequency of a photon of light if the wavelength is 1 x 105 meters?

A) 1 x 1016 Hertz B) 3 x 1016 Hertz C) 3 x 1013 Hertz D) 9 x 1010 Hertz E) 3 x 103 Hertz

11) Kinetic energy is usually given in units of …

A) Newtons B) Joules C) Kilograms D) Hertz E) Gauss

12) You take an image of the sky. On the image, a star has an apparent magnitude of +8, a main-belt asteroid has an apparent magnitude of +6, a Kuiper Belt Object has an apparent magnitude of +17, a Trojan asteroid has an apparent magnitude of +14, and Pluto has an apparent magnitude of +15. Which object is brightest in the sky?

A) The star B) The main-belt asteroid C) The Kuiper Belt Object D) The Trojan asteroid E) Pluto Astronomy 101, Exam #2 Review Astronomy 101, Exam #2 Review

13) Which is not a real advantage of a space-based telescope compared to an Earth-based telescope?

A) It can be open 24 hours and 7 days of week B) The space-based telescope is closer to the objects it studies. C) You do not have to worry about distorting effects of atmosphere D) There is no extra background of light due to scattering of light in the Earth’s atmosphere. E) You can observe in more wavelength regions

14) Why are gamma-ray telescopes located in space and not on the surface of the Earth?

A) Gamma rays are dangerous to humans. B) Gamma rays cannot penetrate the Earth’s atmosphere C) Gamma rays tend to make the telescope radioactive D) Gamma rays penetrate deep into the ground E) Gamma rays do not interact with silicon properly on the surface of the Earth

15) Somebody says that a spectrum of a star appears redshifted. What is happening to the star?

A) The star is getting hotter B) The star is getting colder C) The star is moving towards you. D) The star is moving away from you E) The star is getting larger

16) A star is 10 light years from Earth. The star is moved so it is 5 light years from Earth. How will the apparent brightness of the star change?

A) The apparent brightness will not change B) The apparent brightness will become twice as bright. C) The apparent brightness will become four times as bright D) The apparent brightness will become eight times as bright. E) The apparent brightness will become sixteen times as bright.

17) Different elements always have different numbers of …

A) Neutrons B) Protons C) Isotopes D) Neurons E) Neutrinos Astronomy 101, Exam #2 Review

18) One gram of uranium is completely turned into energy. How much energy is produced?

A) 9 x 1016 Joules B) 3 x 1016 Joules C) 9 x 1013 Joules D) 3 x 1016 Joules E) 1 x 1016 Joules

19) Put these parts of the electromagnetic spectrum in order from shortest wavelength to longest wavelength: Shortest  Longest wavelength

A) Gamma-ray, X-ray, ultraviolet, infrared, visible, radio B) Gamma-ray, X-ray, ultraviolet, visible, infrared, radio C) X-ray, gamma-ray, ultraviolet, visible, infrared, radio D) Radio, gamma-ray, X-ray, ultraviolet, visible, infrared E) Radio, infrared, visible, ultraviolet, X-ray, Gamma-ray

20) Put these parts of the electromagnetic spectrum in order from lowest frequency to highest frequency: Lowest  Highest frequency

A) Radio, infrared, visible, ultraviolet, X-ray, gamma-ray B) Gamma-ray, X-ray, ultraviolet, visible, infrared, radio C) Radio, visible, ultraviolet, X-ray, gamma-ray, infrared D) Gamma-ray, X-ray, ultraviolet, visible, radio, infrared E) Radio, X-ray, infrared, ultraviolet, visible, gamma-ray

21) Put these parts of the electromagnetic spectrum in order from lowest energy to highest energy: Lowest  Highest energy

A) Gamma-ray, X-ray, ultraviolet, infrared, visible, radio B) Gamma-ray, X-ray, ultraviolet, visible, infrared, radio C) X-ray, gamma-ray, ultraviolet, visible, infrared, radio D) Radio, gamma-ray, X-ray, ultraviolet, visible, infrared E) Radio, infrared, visible, ultraviolet, X-ray, Gamma-ray Astronomy 101, Exam #2 Review

22) As the temperature decreases for an object, the peak of the black-body radiation curve measured for the object moves to …

A) lower intensities and longer wavelengths B) higher intensities and shorter wavelengths C) lower intensities and shorter wavelengths D) higher intensities and longer wavelengths E) does not change in intensity or in wavelength position

23) What is a CCD (which stands for charge-coupled device) used for?

A) It is the world's largest operating telescope. B) It refers to any kind of instrument that can be hooked up to a telescope. C) It is an electronic detector that can be used in place of photographic film for taking images of the sky. D) It is a unit used by astronomers to measure angular resolution. E) It is the next telescope that will be launched into space.

24) Which is not a reason why all large modern telescopes tend to be reflectors?

A) It is much easier to make a high-quality mirror than the same quality lens B) Large mirrors are much lighter than large lenses C) Lenses focus different wavelengths of light slightly differently. Mirrors do not have this problem D) Some wavelengths of light can be significantly absorbed by the lens. E) Lenses cannot be used to observe astronomical objects.

25) Which is not a phase of matter?

A) gas B) solid C) liquid D) psion E) plasma

26) The temperature in this room is closest to what temperature in Kelvin?

A) 100 Kelvin B) 200 Kelvin C) 300 Kelvin D) 400 Kelvin E) 500 Kelvin Astronomy 101, Exam #2 Review

27) A prism can be used to break light up into its constituent spectral colors since different wavelengths of light are refracted differently by glass and leave the prism at different angles. What is the order of the colors of light from shortest to longest wavelength? Shortest  Longest wavelength

A) Violet, Indigo, Red, Blue, Green, Yellow, Orange B) Red, Orange, Yellow, Green, Blue, Indigo, Violet C) Red, Yellow, Orange, Blue, Green, Indigo, Violet D) Violet, Indigo, Green, Blue, Orange, Yellow, Red E) Violet, Indigo, Blue, Green, Yellow, Orange, Red

28) Light can act as which of the following?

A) Only as a particle B) Only as an isotope C) Only as a wave D) As a particle and a wave E) Only as an ion

29) Who was the first to propose the formula E=mc2 for converting matter into energy?

A) Isaac Newton B) Albert Einstein C) Henry Cavendish D) Tycho Brahe E) Johannes Kepler

30) Which of these particles take the shortest time to travel from the core of the Sun to the surface of the Sun?

A) gamma ray photon B) positron C) neutrino D) electron E) proton

31) The two most abundant elements in the Sun are?

A) oxygen and carbon. B) iron and hydrogen. C) carbon and iron. D) hydrogen and helium. E) iron and helium. Astronomy 101, Exam #2 Review

32) Which star is closest in distance to the Earth?

A) Alpha Centauri A B) Sirius C) Sun D) Polaris E) Proxima

33) The Hertzsprung-Russell Diagram has ______. (the horizontal axis is the x-axis and the vertical axis is the y-axis)

A) surface temperature (or spectral type) on its horizontal axis and apparent brightness on its vertical axis B) age on its horizontal axis and diameter on its vertical axis C) surface temperature (or spectral type) on its horizontal axis and stellar luminosity on its vertical axis D) diameter on its horizontal axis and lifetime on its vertical axis E) diameter on its horizontal axis and stellar luminosity on its vertical axis

34) Which of these spectral types has the hottest surface temperature?

A) B type B) F type C) G type D) K type E) M type

35) How was the Homestake Gold Mine used to detect neutrinos?

A) The Gold in the mine tends to react with the neutrinos and become radioactive. This radioactivity could be measured B) The mine contains water that undergoes fusion when neutrinos strike it. The resulting heat could be measured C) The mine was filled with a chlorine-containing liquid. When a Chlorine atom captures a neutrino, it becomes radioactive argon, which releases an electron which can be detected by a detector. D) The mine was filled with Argon gas. When an Argon atom captures a neutrino, it becomes radioactive Krypton, which releases an electron which can be detected by a detector. E) The Gold in the mine tends to slow the neutrinos down and allows them to be detected by a neutrino detector. Astronomy 101, Exam #2 Review Astronomy 101, Exam #2 Review

36) The Sun produces energy by the fusion of 4 hydrogen atoms into 1 helium atom. The amount of energy produced can be computed from the equation that relates energy and mass: E = mc2. To compute the energy generated by the fusion of 4 hydrogen atoms, the m in this equation should be

A) the mass of the 4 hydrogen atoms. B) the mass of the 1 helium atom. C) the mass of just 1 hydrogen atom. D) the sum of the masses of the 4 hydrogen atoms and the 1 helium atom. E) the difference in mass between the 4 hydrogen atoms and the 1 helium atom.

37) Main sequence stars tend to have this trait in common with each other.

A) They all tend to fuse Hydrogen into Helium B) They all tend to have similar diameters. C) They all tend to have similar temperatures. D) They all tend to have similar masses. E) They all tend to fuse Helium into Carbon.

38) What is the complete stellar classification of the Sun?

A) M5 V B) M2 I C) G2 V D) B4 V E) K3 III

Use Table 1 for questions 39, 40, and 41

Table 1. Here are some stars and their spectral classification Star Classification Sirius A A1 V Achernar B5 V Aldebaran B M2 V Fomalhaut B K4 V Betelgeuse M2 I

39) Which star is not on the Main Sequence?

A) Sirius A B) Achernar C) Aldebaran B D) Fomalhaut B E) Betelgeuse Astronomy 101, Exam #2 Review

40) Which two stars would you expect to have surface temperatures that are closest in value to each other?

A) Sirius A and Achernar B) Achernar and Fomalhaut B C) Aldebaran B and Betelgeuse D) Fomalhaut B and Sirius A E) Betelgeuse and Fomalhaut B

41) Which star would you expect to be the smallest in mass?

A) Sirius A B) Achernar C) Aldebaran B D) Fomalhaut B E) Betelgeuse

42) Who first proposed that a star’s surface temperature determines the strength of its spectral lines?

A) Edward Pickering B) Albert Einstein C) Cecilia Payne-Gaposchkin D) Marie Curie E) Jocelyn Bell

43) For main sequence stars, the general rule is that the higher the surface temperature, …

A) the more numerous are the stars. B) the greater the masses of the stars. C) the less luminous are the stars. D) the more common are binary stars. E) the longer the lifetime on the main sequence

44) The process by which two or more smaller nuclei slam together and make a larger nucleus is called …

A) Nuclear fission B) Nuclear fusion C) Strong force D) Electron decay Astronomy 101, Exam #2 Review

E) Gravitational equilibrium

45) The total lifetime of the Sun as a main sequence star is approximately

A) one hundred billion (100,000,000,000) years. B) ten million (10,000,000) years. C) one million (1,000,000) years. D) one hundred million (100,000,000) years. E) ten billion (10,000,000,000) years

46) What is the order of the regions of the Sun from the center outward?

A) corona, core, convection zone, radiation zone, photosphere, chromosphere B) core, radiation zone, convection zone, photosphere, chromosphere, corona

C) photosphere, chromosphere, core, radiation zone, convection zone, corona

D) core, radiation zone, corona, convection zone, chromosphere, photosphere

E) radiation zone, core, convection zone, photosphere, corona, chromosphere

47) Suppose two stars are identical except that one star is four times as far away from us as the other star. Which statement is true?

A) Both stars have the same luminosity, but the apparent brightness of the closer star is sixteen times greater than that of the more distant star. B) Both stars have the same apparent brightness, but the luminosity of the closer star is sixteen times greater than that of the more distant star. C) Both stars have the same apparent brightness, but the luminosity of the closer star is four times greater than that of the more distant star. D) Since the stars are identical, they have the same apparent brightness and luminosity. E) Both stars have the same luminosity, but the apparent brightness of the closer star is four times greater than that of the more distant star.

48) Where does fusion take place in the Sun during its main sequence lifetime?

A) convection zone. B) core. C) corona. D) photosphere. E) chromosphere.

49) Which part (or layer) of the Sun has the coldest temperature? Astronomy 101, Exam #2 Review

A) core B) corona C) chromosphere. D) photosphere E) radiation zone