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Astronomy
Test 1 (part 2)
| Question | Answer |
|---|---|
| The most accurate Greek attempt to explain planetary motion was the model of: | Ptolemy |
| The Ptolemaic model probably persisted for all these reasons Except: | it accounted well for Galileo's observations of the phase cycle of Venus |
| The Ptolemaic model of the universe: | explained and predicted the motions of the planets with deferents and Epicycles |
| Scientists today do not accept the Ptolemaic model because: | the work of Tycho and Kepler showed the heliocentric model was more accurate |
| The heliocentric model was actually first proposed by: | Aristarchus |
| Which of these was Not seen telescopically by Galileo? | Stellar parallax. |
| which of the following is a contribution to astronomy made by galileo? | All of the above. |
| Which of these observation of Galileo refuted Ptolemy's epicycles? | the complete cycle of Venus' phases |
| It took two centuries for the Copernican model to replaced the Ptolemaic model because? | there was no scientific evidence to support either model until Galileo made his observations |
| Kepler's first law worked, where Copernicus' original heliocentric model failed, because Kepler described the orbits as: | elliptical, not circular. |
| The most famous prehistoric astronomical observatory is: | Stonehenge |
| A circular orbit would have an eccentricity of | 0 |
| Upon which point do Copernicus and Kepler disagree? | The orbits of the planets are ellipses with one focus at the Sun. |
| What contribution to astronomy was made by Tycho Brahe? | His observations of planetary motion with great accuracy proved circular orbits could not work |
| What does Kepler's third law imply about planetary motion? | Planets further from the Sun orbit at a slower speed than planets closer to the Sun. |
| A planet whose distance from the Sun is 3 A.U. would have an orbital period of how many Earth-years? | √27 |
| The place in a planet's orbit that is closest to the Sun is called | perihelion. |
| The force of gravity varies with the: | (A and C are correct) product of 2 masses and inverse square of the distance separating the two bodies |
| The law of universal gravitation was developed by | Newton |
| According to Newton's Law of Universal Gravitation if the moon were three times further from Earth the force by Earth on the Moon would: | decreases by a factor of 9 |
| How much stronger is the gravitational pull of the Sun on Earth, at 1 AU, than it is on Saturn at 10 AU? | 100X. |
| Which of these was a contribution of Newton to astronomy? | His differential calculus lets us calculate planetary motions more accurately. Sun's gravity is greatest on a planet at perihelion, so the planet must speed up. Artificial satellites could be put into orbit about the Earth. Moon pulls as strongly on us |
| Jupiter lies about 5 A.U. from the Sun, so at its distance: | the Sun's gravity is 25 times weaker than its pull on the Earth. |
| If the distance between two asteroids is doubled, the gravitational force they exert on each other will | be one fourth as great. |
| Escape velocity is the speed required to | overcome the gravitational pull of an object. |
| According to Copernicus, retrograde motion for Venus must occur around | inferior conjunction, when it passes between us and the Sun. |
| Kepler's second law implies what about planetary motion? | A planet moves faster when it is closer to the Sun. |