Astronomy I Exam I Sample Name: Read each question carefully, and choose the best answer.

Transcription

1 Name: Read each question carefully, and choose the best answer. 1. As seen from Schuylkill Haven, the sun, moon stars and planets, over the course of an evening, will tend to (A) do different things depending upon the season. (B) the sun rises in the east and sets in the west, the others rise in the west and set in the east.. (C) rise in the east and set in the south. (D) rise in the east and set in the west. 2. A line on a sphere (like the celestial sphere) that divides it into two equal halves is (A) a Great Circle. (B) can be used to set a zero point for a coordinate system (C) can be seen in the examples of the earth's equator, the horizon and the celestial equator 3. The point directly over an observer's head is that observer's (A) horizon. (B) zenith. (C) equator. (D) azimuth. 4. The angular distance of an object from the horizon is its (A) latitude. (B) declination. (C) altitude. (D) right ascension. 5. A finger, held at arm's length, fills an angle of about (A) 10 degrees (B) 2 degrees (C) ½ degree (D) a minute 6. The angular size of the Sun and Moon are both about (A) ½ a degree. (B) ½ of a great circle. (C) ½ of an angstrom. (D) ½ a second. 7. The line marking the great circle that divides the celestial sphere into northern and southern hemispheres is the (A) Ecliptic (B) Celestial equator (C) Meridian (D) Horizon 1

2 8. As seen from Schuylkill Haven, Circumpolar stars (A) move in a counterclockwise motion in the sky. (B) are located in the region of the sky centered about Polaris. (C) never set. 9. The daily motion of an object (like the sun) relative to the horizon is its (A) diurnal motion (B) synodic motion (C) syntactic motion (D) perpetual motion 10. The main difference between the planets and the stars when viewed with the naked eye is that (A) the planets move relative to the stars. (B) the planets cannot be seen with the naked eye because they are too far away. (C) the planets never move relative to each other. (D) the planets are all much brighter looking than stars. 11. The Sun's annual path on the celestial sphere is the which takes it through the. (A) Ecliptic, Zodiac. (B) Zenith, Planets. (C) Equator, Tropics. (D) Meridian, Celestial Poles. 12. A planet's temporary backward motion relative to the stars, illustrated at right, is called (A) retrograde motion. (B) the big crunch (C) closed geometry. (D) elliptical motion. 13. At approximately what time does the Full Moon set? (A) sunset (B) sunrise (C) noon (D) midnight 14. In Schuylkill Haven, on the day of the Winter Solstice (compared to any other day of the year) (A) the sunrise is as farthest south (B) the number of daylight hours is the least (C) the altitude of the sun at local noon (meridian crossing) is the lowest (D) all of the above 15. Relative to the stars, the Moon (A) remains stationary. (B) moves eastward, then westward during a month. (C) moves westward. (D) moves eastward 2

3 16. Local noon corresponds to the time when the Sun is on the (A) Zenith. (B) Meridian. (C) Nadir. (D) Ecliptic. 17. A shift in the direction of an object caused by a change in the position of an observer is called (A) precession. (B) the Coriolis effect. (C) parallax. (D) epicycle motion. 18. Which of the following was not a product of Babylonian Astronomy? (A) Accurate tables of planetary positions. (B) recognition of variations in the planetary cycles. (C) arithmetic methods of predicting planetary positions. (D) a detailed model of the solar system. 19. Which of the following is a reason that the ancient Greek astronomers rejected Aristarchus' heliocentric model of the solar system? (A) it did not account for retrograde motions of the planets (B) it could not explain the phases of Venus (C) they could detect no stellar parallax (D) it could not account for the Coriolis effect 20. Eratosthenes compared the altitude of the noon sun at different locations in order to determine (A) the circumference of the Earth. (B) the size of the sun. (C) the relative distance of the sun and the moon. (D) the length of the synodic day. 21. What body was located at the center of Ptolemy's model of the solar system? (A) The Sun (B) The Moon (C) The Earth (D) The central fire 22. Ptolemy used epicycles (illustrated at right) to explain (A) retrograde motion. (B) the equation of time. (C) circumpolar motion. (D) eclipses. 23. When Galileo observed Venus with his telescope, he saw something that didn t fit the Ptolemaic model for the Solar System. What was it? (A) He saw Venus go through phases (like the moon) that were impossible in Ptolemy's model. (B) He saw craters on the surface of Venus instead of the perfectly smooth surface a heavenly body should have. (C) He saw that Venus did not actually undergo retrograde motion. (D) He saw someone on Venus looking back at him with their own telescope. 3

4 24-27) Match the element of the Copernican model below with its observation consequence: A. Earth overtakes Object. B. Earth's motion around object. C. Motion of object around earth. D. Earth rotates. 24. Mars undergoing retrograde motion 25. The sun moves west to east along the ecliptic 26. The moon's monthly motion 27. The sun moves east to west daily 28. Which of the following best completes this sentence: When tested against the observed motion of the planets, (A) Ptolemy s model was least accurate, Kepler s was more accurate and Copernicus s was most accurate. (B) Ptolemy s model was least accurate, Copernicus s was more accurate and Kepler s was most accurate. (C) Ptolemy s model was most accurate, Copernicus s was less accurate and Kepler s was least accurate. (D) Ptolemy s model and Copernicus s were about equally accurate, and Kepler s was more accurate 29. Where did Kepler get the data used to create his 3 laws of planetary motion? (A) Observations of the Ancient Babylonians. (B) His own telescopic observations. (C) Tycho Brahe. (D) He made the data up. 30. The Sun is located at one focus of the orbit of a planet. What is located at the other focus? (A) Nothing (B) The Earth (C) The planet itself (D) One of the other planets 31. Kepler's law of equal areas in equal times predicts that (A) Planets move fastest at perihelion. (B) Comets are often in unbound orbits. (C) The sun must be at the center of the solar system. (D) Planets are in noncircular orbits. 32. Newton's great breakthrough in how he viewed the cosmos was that he (A) applied the same physical laws in the sky and on Earth. (B) viewed gravity as a mysterious force between masses. (C) thought that natural motion was distinct from forced motion. (D) determined that the universe as infinite in extent. 4

5 33. For an object to accelerate it must (A) change its speed (B) change its direction of motion (C) change its speed and direction of motion. (D) change its speed or direction of motion (or both) 34. Suppose an object moves in a circular path at constant speed. What can be said about the force acting on it? (A) the force is directed towards the center of the circle (B) the force acting on it has constant strength (C) both (A) and (B) (D) none of the above is correct 35. If the distance between two objects is decreased, the force of gravity they exert on each other will (A) remain the same (B) increase (C) decrease (D) vanish 36. Newton's theory of Universal Gravitation, combined with mechanics (A) was important because it described both earthly and cosmic phenomena using the same principles. (B) explained falling objects and projectile motion. (C) explained Kepler's Laws. 37. The strongest tides occur during the. (A) fall and spring (B) new and full phases of the moon (C) mid afternoon and late night (D) 37 th question of the exam 38. Kinetic energy (A) is the energy associated with the gravitational attraction of an object by another object (B) is the same thing as electric charge (C) is the energy associated with the motion of an object (D) is responsible for the retrograde motion of stars 39. A particle of light is a (A) graviton (B) photon (C) angstrom (D) neutrino 40. Which form of electromagnetic waves (or photons) has the least energy? (A) the wave with the smallest frequency. (B) the wave with the largest frequency. (C) frequency and energy have nothing to do with each other. (D) trick question, photons exist only in the minds of the writers of Star Trek. 5

6 41. Which of the following principles from Optics are relevant to telescopes? (A) Refraction (light rays bend at interfaces). (B) Reflection (light rays bounce at surfaces). (C) Diffraction (light waves bend around corners). (D) all of the above 42. A telescope that uses a mirror to collect light is called a (A) radio telescope (B) reflector (C) refractor (D) photometer 43. The same telescope is used to obtain an image using light of the following wavelengths. Which of the images will have the best angular resolution? (A) Violet (shortest wavelengths) (B) Blue (short-medium wavelengths) (C) Yellow (medium wavelengths) (D) Red (longest wavelengths) 44. The process in which heat is transported from one place to another by means of electromagnetic waves is called (A) radiative transfer (B) convection (C) conduction (D) fusion 45. Which of the following planets is most likely to retain a thick atmosphere? (A) a planet with a hot atmosphere, low gravity. (B) a planet with a hot atmosphere, high gravity. (C) a planet with a cool atmosphere, low gravity (D) a planet with a cool atmosphere, high gravity. 46. What happens to the electromagnetic radiation emitted by a blackbody if the blackbody gets hotter? (A) It would get redder and dimmer (B) It would get redder and brighter (C) It would get bluer and dimmer (D) It would get bluer and brighter 47. In what process does a nucleus split apart into smaller pieces while releasing energy? (A) fission (B) fusion (C) radioactivity (D) convection 6

7 48. In an atmosphere composed of a mixture of gases at a particular temperature, the molecules that move slowest are those that have (A) the biggest diameter (B) the largest chemical formula (C) the most mass (D) the least mass 49. The most abundant elements in the solar system are (A) Carbon and Water. (B) Hydrogen and Iron. (C) Iron and Nickel. (D) Hydrogen and Helium. 50. For unstable nuclear isotopes which decay (A) known decay rates of materials found within a sample can be used to determine the age of the sample. (B) energy is released in every spontaneous decay. (C) the rate at which the nuclei decay is described in terms of the isotope s half-life. (E) none of the above. 7