Test 1 Review Chapter 1 Our place in the universe

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1 Test 1 Review Bring Gator 1 ID card Bring pencil #2 with eraser No use of calculator or any electronic device during the exam We provide the scantrons Formulas will be projected on the screen You can use the exam sheets as scrap paper if you need to do calculations. The exam has 35 questions. 5 possible answers, only one valid answer. Material for Exam #1: Ch1, Ch S1, Ch 2, Ch 3, and first part of Ch4 Exam will be in room FLG 230, on Tuesday February 12 at 10:40 AM Please arrive on time. You may not be able to take the exam if you arrive after the first person turn in the exam. Chapter 1 Our place in the universe Topics Our place in the universe. The Earth, the solar system, the Milky way, the Local cluster of galaxies, super clusters of galaxies. Our cosmic address. Which are the elements created during the Big Bang? Where are the heavier elements created? The speed of light. The light year Looking back in time. Looking at distant objects means looking at objects as they were when light left the object. Because of the finite speed of light it means looking back in time. The motions of the Earth. Rotation, orbital motion, motion of the solar system, rotation of the Milky Way galaxy What is the ecliptic? What is the tilt of the Earth rotational axes respect to a perpendicular to the Earth orbital plane The expansion of the universe

2 Questions What is our cosmic address? What is the AU? Which are the elements created in the Big Bang. Where are the heavier elements created How long takes light to reach the Moon, the Sun, the nearest star? What is a light year? If we see a galaxy that is ten times as far than another galaxy, the light from which one of the two traveled the longer distance? Assuming that both were born at the same time, which one of the two will look younger to us? Are we the center of the universe? What did Hubble discovered? Relationship between velocity of recession and distances to galaxies

3 Chapter 2 and S1 The celestial sphere, coordinates system, seasons, phases of the moon, eclipses Basics of the celestial sphere The celestial equator, celestial poles, the ecliptic Right Ascension (RA) and Declination (Dec). Altitude and Azimuth. What are the equinoxes and solstices Solar and sidereal days The ecliptic What is a constellation Where are the constellations of the Zodiac located Understand the reason for the seasons. Lunar phases and relative positions of Sun, Moon and Earth for different phases What does it mean that the moon had a synchronous rotation? Tidal locking Solar and lunar eclipses (locations and relative positions of Earth-Moon-Sun) Types of Solar eclipses: Total, partial and annular Precession Questions Where is the celestial pole and the celestial equator for an observer at the equator? For an observer at the north pole? How can we estimate our latitude? What is the declination of the Sun for the equinoxes. For the solstices What causes the season? Is it the changing distance of the Earth to the Sun? Do we have winter or summer in the north and southern hemisphere at the same time? How many degrees is the tilt of the Earth rotational axis respect to a perpendicular to the orbital plane?

4 Chapter 2 and S1 The celestial sphere, coordinates system, seasons, phases of the moon, eclipses Questions Does the earth remains at the same distance from the Sun during the year? When are the approximate dates for the equinoxes and solstices? What is precession? How long is the cycle of Earth precession? Will always Polaris be the North star? What causes the phases of the Moon? What is the relative location of the Moon, Sun and Earth for the different phases of the Moon? Were is the Sun respect to the Moon when it is full moon. Where is the Sun when it is new moon? Why do we see the same face of the Moon? Where is the Moon respect to the Sun s position for a lunar eclipse? For a solar eclipse? Why we don t have lunar and solar eclipses every month? What is the tilt angle of the rotational axis of the Earth respect to the perpendicular to the orbital plane? What will happen in the future to the position of Polaris respect to the north pole due to precession?

5 Chapter 2-3 The Copernican revolution Topics What were the planets know in ancient times? Planets apparent retrograde motion Stellar parallax What are Ptolemy, Copernicus, Brahe, Kepler and Galileo contribution to Astronomy? The Kepler s three laws of planetary motion. 1 st law: Planets move in orbit around the Sun in elliptical orbits. 2 nd Law: Planets sweep equal areas in equal interval of time. 3 rd Law: p 2 = a 3 What did Galileo discover with his telescope? How Galileo observations solidified the heliocentric model? How important was Galileo discovery of the four moon orbiting Jupiter How important was his observations of Venus phases? Distinction between science, non-science. The scientific method Difference between astronomy and astrology Questions: Which planets were known to Ptolemy, Copernicus, Brahe, Kepler and Galileo? What is retrograde motion and how did early earth-centered models account for it? How do we explain now the retrograde motion? Why the Greeks didn t detect stellar parallax? Why Tycho Brahe didn t detect stellar parallax What are the 3 Kepler s laws of planetary motion? Four important discoveries Galileo did with his telescope? How is the retrograde motion explained in a heliocentric model?

6 Chapter 4 Motion, energy, gravity Topics Speed, velocity, acceleration Acceleration of gravity Linear (m x v) and angular (m x r xv) momentum Conservation of linear momentum Conservation of angular momentum Concept of mass and weight Why are astronauts weightless in space The three Newton s laws of motion 1 st Law: An object moves at constant velocity unless a net force acts to change its speed or direction. 2 nd Law: F = m a 3 rd Law: For every force, there is always an equal and opposite reaction force. Questions How is you mass and weight changed if you are on the surface of Jupiter What will happens to an object moving at a constant velocity if no force is applied to it? What will happens to the velocity of an object if we apply a constant force? Are astronauts weightless in space because there is no gravitational force acting upon them? Why are planets orbiting the Sun. Are they in a constant state of free-fall? What happens when an skater is spinning and fold his/her arms? What it is conserved here?