* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Download The core of the Sun is
Planets beyond Neptune wikipedia , lookup
Outer space wikipedia , lookup
Observational astronomy wikipedia , lookup
IAU definition of planet wikipedia , lookup
Aquarius (constellation) wikipedia , lookup
Astrobiology wikipedia , lookup
Geocentric model wikipedia , lookup
Rare Earth hypothesis wikipedia , lookup
Definition of planet wikipedia , lookup
Galilean moons wikipedia , lookup
History of Solar System formation and evolution hypotheses wikipedia , lookup
Extraterrestrial skies wikipedia , lookup
Formation and evolution of the Solar System wikipedia , lookup
Late Heavy Bombardment wikipedia , lookup
Comparative planetary science wikipedia , lookup
Astronomical unit wikipedia , lookup
Extraterrestrial life wikipedia , lookup
Dialogue Concerning the Two Chief World Systems wikipedia , lookup
The core of the Sun is 1) 2) 3) 4) 5) at the same temperature and density as the surface. at the same temperature but denser than the surface. hotter and denser than the surface. constantly rising to the surface through convection. composed of iron. Sunspots are cooler than the surrounding solar surface because 1. they are regions where convection carries cooler material downward. 2. strong magnetic fields slow convection and prevent hot plasma from entering the region. 3. magnetic fields trap ionized gases that absorb light. 4. there is less fusion occurring there. 5. mag How does the Sun generate energy today? 1. 2. 3. 4. 5. nuclear fission nuclear fusion chemical reactions gravitational contraction gradually expanding in size How do human-built nuclear power plants on Earth generate energy? 1. 2. 3. 4. chemical reactions nuclear fusion nuclear fission converting kinetic energy into electricity 5. converting gravitational potential energy into electricity At the center of the Sun, fusion converts hydrogen into 1. hydrogen compounds. 2. plasma. 3. radiation and elements like carbon and nitrogen. 4. radioactive elements like uranium and plutonium. 5. helium, energy, and neutrinos. Suppose you put two protons near each other. Because of the electromagnetic force, the two protons will 1. collide. 2. remain stationary. 3. attract each other. 4. repel each other. 5. join together to form a nucleus. Since all stars begin their lives with the same basic composition, what characteristic most determines how they will differ? 1. 2. 3. 4. 5. location where they are formed time they are formed luminosity they are formed with mass they are formed with color they are formed with A star's luminosity is the 1. apparent brightness of the star in our sky. 2. surface temperature of the star. 3. lifetime of the star. 4. total amount of light that the star will radiate over its entire lifetime. 5. total amount of light that the star radiates each second. The spectral sequence sorts stars according to 1. 2. 3. 4. 5. mass. surface temperature. luminosity. core temperature. radius. Which of the following terms is given to a pair of stars that appear to change positions in the sky, indicating that they are orbiting one another? 1. 2. 3. 4. 5. visual binary eclipsing binary spectroscopic binary double star none of the above Which of the following best describes the axes of a Hertzsprung-Russell (H-R) diagram? 1. surface temperature on the horizontal axis and luminosity on the vertical axis 2. mass on the horizontal axis and luminosity on the vertical axis 3. surface temperature on the horizontal axis and radius on the vertical axis 4. mass on the horizontal axis and ste On a Hertzsprung-Russell diagram, where would we find stars that are cool and dim? 1. 2. 3. 4. upper right lower right upper left lower left On a Hertzsprung-Russell diagram, where would we find red giant stars? 1. 2. 3. 4. upper right lower right upper left lower left Which of the following statements about comets and asteroids is true? 1. Only asteroids collide with Earth. 2. Comets are balls of ice and dust. 3. Most of the trillions of comets in our solar system have tails. 4. All asteroids lie in the asteroid belt between Mars and Jupiter. 5. There are about 1 million known asteroids in the solar system Why do asteroids and comets differ in composition? 1. Asteroids formed inside the frost line, while comets formed outside. 2. Asteroids and comets formed at different times. 3. Comets formed from the jovian nebula, while asteroids did not. 4. Comets are much larger than asteroids. 5. Asteroids are much larger than c If an object's velocity is doubled, its momentum is 1. 2. 3. 4. 5. halved. unchanged. doubled. quadrupled. dependent on its acceleration. You are standing on a scale in an elevator. Suddenly you notice your weight decreases. What do you conclude? 1. The elevator is accelerating upwards. 2. The elevator is moving at a constant velocity upwards. 3. The elevator is accelerating downwards. 4. The elevator is moving at a constant velocity downwards. 5. Your diet is working. What quantities does angular momentum depend upon? 1. 2. 3. 4. 5. mass and velocity mass, velocity, and radius force and radius force, velocity, and radius momentum and angular velocity The amount of gravitational potential energy released as an object falls depends on 1. the distance it falls. 2. its speed at the time it begins falling. 3. the distance it falls and its speed at the time it begins falling. 4. neither the distance it falls nor its speed at the time it begins falling. Which of the following statements correctly describes the law of conservation of energy? 1. An object always has the same amount of energy. 2. Energy can change between many different forms, such as potential, kinetic, and thermal, but it is ultimately destroyed. 3. The total quantity of energy in the universe never changes. 4. The fact that you can fuse hydrogen into helium to produce energy means that helium can be turned into hydrogen to produce energy. According to what we now know from Newton's laws, which of the following best explains why Kepler's second law is true? 1. A planet's total orbital energy must be conserved as it moves around its orbit. 2. Orbits must be elliptical in shape. 3. Gravity is an inverse cube law. 4. This effect happens because of the influence of other planets on a particular planet's orbit. The mass of Jupiter can be calculated by 1. measuring the orbital period and distance of Jupiter's orbit around the Sun. 2. measuring the orbital period and distance of one of Jupiter's moons. 3. measuring the orbital speed of one of Jupiter's moons. 4. knowing the Sun's mass and measuring how Jupiter's speed changes during its elliptical orbit around the Sun. The frequency of a wave is 1. the number of peaks passing by any point each second. 2. measured in cycles per second. 3. measured in hertz (Hz). 4. equal to the speed of the wave divided by the wavelength of the wave. 5. all of the above The wavelength of a wave is 1. how strong the wave is. 2. the distance between a peak of the wave and the next trough. 3. the distance between two adjacent peaks of the wave. 4. the distance between where the wave is emitted and where it is absorbed. 5. equal to the speed of the wave times the When an atom loses an electron, it becomes 1. 2. 3. 4. 5. sublimated. dissociated. ionized. an isotope. a plasma. How can an electron in an atom lose energy to go from a higher energy level to a lower energy level? 1. It loses kinetic energy. 2. It releases a light equal in energy to its own energy drop. 3. It absorbs a light equal in energy to its own energy drop. 4. It loses gravitational potential energy. 5. It exchanges gravitational potential energy for kinetic energy. Everything looks red through a red filter because 1. the filter emits red light and absorbs other colors. 2. the filter absorbs red light and emits other colors. 3. the filter transmits red light and absorbs other colors. 4. the filter reflects red light and transmits other colors. Which of the following statements about X rays and radio waves is not true? 1. Neither X rays nor radio waves can penetrate Earth's atmosphere. 2. X rays have shorter wavelengths than radio waves. 3. X rays and radio waves are both forms of light, or electromagnetic radiation. 4. X rays have higher frequency than radio waves. 5. X rays have higher energy than radio waves. We can see each other in the classroom right now because we 1. 2. 3. 4. 5. emit thermal radiation. emit visible light. emit infrared light. reflect visible light. reflect infrared light. If you heat a gas so that collisions are continually bumping electrons to higher energy levels, when the electrons fall back to lower energy levels the gas produces 1. 2. 3. 4. 5. thermal radiation. an absorption line spectrum. an emission line spectrum. X rays. radio waves. Where does nuclear fusion occur in the Sun? 1. 2. 3. 4. 5. on the surface anywhere below the surface in its core just above the visible surface all of the above Which planet has the highest average surface temperature, and why? 1. Mercury, because it is closest to the Sun 2. Mercury, because of its dense carbon dioxide atmosphere 3. Venus, because of its dense carbon dioxide atmosphere 4. Mars, because of its red color 5. Jupiter, because it is so big Which planet has a ring system? 1. 2. 3. 4. 5. Jupiter Saturn Uranus Neptune All of the above Which of the following is not a characteristic of the inner planets? 1. They are relatively smaller than the outer planets. 2. They all have solid, rocky surfaces. 3. Their orbits are relatively closely spaced. 4. They all have substantial atmospheres. 5. They have very few, if any, satellites. The farthest bright galaxies that modern telescopes are capable of seeing are up to 1. 2. 3. 4. 5. 1 million light years away 10 million light years away 1 billion light years away 10 billion light years away 1 trillion light years away Earth is made mostly of metals and rocks. Where did this material come from? 1. 2. 3. 4. 5. It was produced in the Big Bang. It was created by chemical reactions in interstellar space. It was produced by nuclear fusion in stars. It was made by our Sun. It was made by nuclear fission of uranium and other radioactive materials Suppose we look at a photograph of many galaxies. Assuming that all galaxies formed at about the same time, which galaxy in the picture is the youngest? 1. the one that is farthest away 2. the one that is reddest in color 3. the one that is bluest in color 4. the one that is closest to us 5. the one that appears smallest in size Our solar system is located in the center of the Milky Way Galaxy. 1. True 2. False Which of the following statements about the celestial equator is true at all latitudes? 1. 2. 3. 4. 5. It lies along the band of light we call the Milky Way. It represents an extension of Earth's equator onto the celestial sphere. It cuts the dome of your local sky exactly in half. It extends from your horizon due east, through your zenith, to your horizon due west. It extends from your horizon due north, through your zenith, to your horizon due south. If it is midnight in New York, it is 1. 2. 3. 4. 5. daytime in Sydney, Australia. midnight in Sydney, Australia. midnight in Los Angeles. midday in Rio de Janeiro, Brazil. midnight everywhere. Orion is visible on winter evenings but not summer evenings because of 1. 2. 3. 4. 5. interference from the full moon. the tilt of Earth's axis. the location of Earth in its orbit. the precession of Earth's axis. baseball on television. If the Moon is setting at 6 A.M., the phase of the Moon must be 1. 2. 3. 4. 5. first quarter. third quarter. full. new. waning crescent. At approximately what time would a full moon be on your meridian? 1. 2. 3. 4. 5. 6 A.M. 9 A.M. noon 6 P.M. midnight Which of the following statements about the Moon is true? 1. 2. 3. 4. 5. The Moon goes through a cycle of phases because it always has the same side facing Earth. If you see a full Moon from North America, someone in South America would see a new moon. The Moon's distance from Earth varies during its orbit. The Moon is visible only at night. The side of the Moon facing away from Earth is in perpetual darkness. What effect or effects would be most significant if the Moon's orbital plane were exactly the same as the ecliptic plane? 1. 2. 3. 4. 5. Solar eclipses would be much rarer. Solar eclipses would be much more frequent. Total solar eclipses would last much longer. both 1 and 3 both 2 and 3 What happens during the apparent retrograde motion of a planet? 1. 2. 3. 4. 5. The planet rises in the west and sets in the east. The planet appears to move eastward with respect to the stars over a period of many nights. The planet moves backward through the sky. The planet moves backward in its orbit around the Sun. The planet moves through constellations that are not part of the zodiac. We can't detect stellar parallax with naked-eye observations. Which of the following would make parallax easier to observe? 1. 2. 3. 4. 5. increasing the size of Earth's orbit speeding up Earth's orbital motion slowing down Earth's orbital motion Speeding up the precession of Earth's axis getting away from streetlights Why did Ptolemy have the planets orbiting Earth on "circles upon circles" in his model of the universe? 1. 2. 3. 4. 5. to explain why more distant planets take longer to make a circuit through the constellations of the zodiac to explain the fact that planets sometimes appear to move westward, rather than eastward, relative to the stars in our sky to explain why the Greeks were unable to detect stellar parallax To properly account for the varying distances of the planets from Earth To explain why Venus goes through phases as seen from Earth He developed a system for predicting planetary positions that remained in use for some 1,500 years. 1. 2. 3. 4. 5. Tycho Brahe Copernicus Kepler Galileo Ptolemy He discovered that the orbits of planets are ellipses. 1. 2. 3. 4. 5. Tycho Brahe Copernicus Kepler Galileo Ptolemy One of the "nails in the coffin" for the Earth-centered universe was 1. 2. 3. 4. 5. the retrograde motion of the planets. the phases of the Moon. eclipses of the Sun. Galileo's observation of stars in the Milky Way. Galileo's observations of the moons of Jupiter.