Exam 1 Key B

vame____ KN B New York University History of the Universe First Exam, October 18, 2023 Dr. Gerceida Jones 1. Give at least three examples of how the Newtonian picture was described in the New Universe and Human Future textbook? D D l b @Cqbia. QPO‘\C,@ O}VES‘I'OV) % " ‘DJ‘OJ)S qu Cogmalafi;cqi priney Pa ) 34 coSmo Shes+ Aual - physica ) polonger Hhe Spiritual | 2. If Earth were upright with no tilt, would the”temperature at your location in January be cooler, warmer or the same as it Is currently during @ the month of January? a) cooler @ warmer c) the same 3. Earth's rotational period refers to how long it takes for B a) the Earth to go around the sun once & the Earth to spin on its own axis once c) Moon to go around the Earth once 4. How did the Ptolemaic model explain the apparent retrograde motion of the planets? a) It held that sometimes the planets moved backward along their circular orbits. b) It varied the motion of the celestial sphere so that it sometimes moved C/ backward. It held that the planets moved along small circles that moved on larger circles around the earth. d) It placed the Sun at the center so that the planets’ apparent retrograde motion was seen as the earth passed each one in its orbit. 5. A spinning figure skater spins faster as he/she brings his/her outstretched arms inward. This is an ilustration of the physical principle underlying: a) Kepler's first law. B Kepler's second law. c) Kepler's third law. d) the law of gravity. e) none of the above. 6. What is an astronomical unit? a) the average speed of the Earth around the Sun. b) the length of time it takes the Earth to revoive around the Sun. C/ @ the average distance from the earth to the Sun. d) the diameter of the Earth’s orbit around the Sun. 7. (Short answer): List the sequence of moon phases as they will occur one after the other within one cycle of phases starting with a new moon: + o NeW Moon WANING ¢pescent | &= G{_um(srer' waxing (o1 V05 | Sull Moon, waning qibbo, 3 ch’tué\fi*eo’,wam'nfi ¢ feseent

8. Which statement does pot.use the term light-year in an appropriate way? a) It's about 4 light-years from Earth to Alpha Centauri. It will take me light-years to complete this homework assignment. % c) A light-year is about 10 trillion kilometers. d) The Milky Way Galaxy is about 100,000 light-years in diameter. 9a). How long does it take the Moon to complete one orbit? , m@ How many of the phases will the Moon have gone through in this time? 7 9b). How much of the Moons total surface is illuminated when it is in the New Phase? 1’7- 9c¢). How much of the illuminated surface of the Moon is visible from Earth when it is in the Waxing Crescent Phase? \[ ':[ Waxing Gibbous Phase? 10. All the planets in the solar system revolve in the same direction as they orbit the Sun. True b) False 11. (Short Answer): Explain why the moon goes through phases. 1 : s As 1+ ocbits 2acth e See Van ou portions €vowm Zartwn. 12-13. Please answer the question below: (worth 6 points) Match the scientist with achievement: a) Pythagoras L. Heliocentric Model b) Aristotle 4 Geocentric Model c) Copernicus g Calculated the Circumference of Earth d) Galileo "R _Formed foundation for Greek Astronomy e) Brahe X0 Earth, Wind, Fire, and Water f) Ptolemy €. Greatest naked eye astronomer g) Eratosthenes d_First to use a telescope

18. (Short Answer): What is the Universe? fl’\ e. S um "’@ + a \ o all matteyr o energy ) 19. Ptolemy’s madel placed the planets in orbits called @ CN¢ 5on orbits called Jgfie«g’ N4 S all around Earth. 20. Two Moons orbit a much larger planet. Moon Europa orbits at radius r. Moon Ganymede orbits at radius 4r, How does the planets pull of gravity gn each of the moons compare? ¢a W\Qd& a) It Is 2 times weaker for moon Europa. fflf@ q | b) It is 4 times weaker for moon Europa. __L_ [P c) It is 4 times weaker for moon Ganymede. é 2 e L‘ 7 d) It is 16 times weaker for moon Ganymede. . L. 21. (Short Answer): Contrast Ptolemy’s model of the universe with Ans o h© Copernicus’, 'F{-ol@ W\\-\ _ (j‘@&(‘/e‘/\‘(”o m@dé((édfl*if\(él’l%) | Lopernicug - heliocentvi o ( sun atr the center) | 22. Label the umbra and the penumbra in the picture below. D pe LAMVNCO s 23. What is the relevance of the magnetosphere. TH protects us £rom e solac Wind and otoe ¢ hamcul partictes €rom +he Sun: 24, (PROBLEM): Imagine that a new asteroid was discovered orbiting the Sun. When the asteroid is closest to the Sun, its orbit has a radius Ry = 4.5 AU. When the asteroid is farthest from the Sun, it has a radius of R: = 6.8 AU, how long will it take to orbit the sun? Using Kepler’s 3" Law: d*= T? (Hint: Don’t forget to take Ravg)

25. (Short answer): Name the interior structure of the sun Core radiadion Zone. Conveetive €one Name the exterior structure of the sun photosphe re Chromos’flhwe Corona 26. In what direction is the observer facing? /\/ o (“* \/-\ Figure 2 Sphere 27. (Short answer): Name and explain the different ancient cultural cosmologies we discussed in class: boqdon < ig\\\lp\Ham Hefgabé{ i Keen AsteOnomeo 3gact structure s BpartSTOACHIYE, Countey -Maly ¢ [at farth-god 6l Clat ¢a ‘r~L[,\ Ap S, 0109,-—300\5|/\M spate in hotwe e n (PROBLEM): Calculate the mass of Earth (Units: kg). Given: Mass of a rock sample = 70 g or 0.07 kg Volume of rock sample = 25 cm? or 2.5 x 10714 km? y2 Volume of Earth = 1.02 x 102 km3 o-m'z 007kg = 2§N0Y v - 2 o3 2,6 %10 " km Km - OV — v . Y ‘ = (g,{;)()@_@ J,02 ><>o’244m3): 286 X0 Kj

Bonus Questions: (1 point each) 1. E ¥ D 4. s Kepler's third law, p? = a3, means that a) A planet’s period does not depend on the eccentricity of its orbit. b) Alt orbits with the same semimajor axis have the same period. c) The period of a planet does not depend on its mass. d) Planets that are farther from the sun move at slower average speeds than nearer planets. All of the above are correct. - All the following statements are true. Which one follows directly from Kepler’s third law? a) Venus is more massive than Mercury. Venus orbits the Sun at a slower average speed than mercury. Venus is farther from the Sun than Mercury. ) Venus has a thicker atmosphere than Mercury. The ancient goal of astrology was to a) Understand the origin of the earth. b) Make a more accurate model of the universe. Predict the passing of the seasons. Predict human events. e) Antagonize astronomers. Which of the following is not one of, nor follows directly from, Kepler's Laws? a) The orbit of each planet about the sun is an ellipse with the sun at one focus. As a planet moves around Its orbit, it sweeps out equal areas in equal times. The force of attraction between any two objects decreases with the square of the distance between their centers. d) A planet travels faster when it is nearer to the Sun and slower when it is farther from the Sun. e) More distant planets move at slower speeds.