Solar System Physics 1

1. Solar System Physics 1 Multiple Choice Questions

2. Test Question Does this quiz work? A. Yes B. No

3. Solar System Physics 1 • 1. The radius of the sun is equivalent to… • 10 earth radii. • 100 earth radii. y • 1000 earth radii. • 10000 earth radii.

4. Solar System Physics 1 • 2. Is the gravitational constant, G (6.673 x 10-11) a vector or a scalar? • Vector. y • Scalar.

5. Solar System Physics 1 • 3. A U.F.O hovers stationary above the Earth’s surface at a height of 1km. Assuming gEarth is 9.80 ms-1, and that the Earth is spherically symmetric, what value will g be for the alien? • Just over 9.80 ms-1. • Can’t say, it depends on the mass of the U.F.O. • Just under 9.80 ms-1. y • Exactly the same, g doesn’t depend on altitude.

6. Solar System Physics 1 • 4. The Earth is not spherically symmetric, from where is the value of 9.80 ms-1 for g obtained? • The equator. • The geographic poles. • The magnetic poles. • The average across the whole Earth. y

7. Solar System Physics 1 • 5. How is the gravitational force between two masses proportional to r, the distance between them? • 1/r. • 1/r2. y • The force is independent of r. • None of the above.

8. Solar System Physics 1 • 6. Venus has a mass of 0.815 Earth masses and a radius of 0.949 Earth radii. Is its escape velocity… (recall how the escape velocity is proportional to mass and radius.) • Not enough information to decide. • Less than Earth’s. y • Greater than Earth’s.

9. Solar System Physics 1 • 7. A high velocity rifle can fire a bullet at 1000 m/s in a vacuum. If this were fired vertically upwards from the Earth, Mercury and Jupiter, from which planet will the bullet go into orbit? You can assume all have no atmosphere! • None of them. y • Mercury only. • Mercury and the Earth only. • All three.

10. Solar System Physics 1 • 8. A man with a mass of 100.000 kg says that he only weighs himself when the moon is directly overhead because the tidal force due to the moon has the effect of reducing his weight by 1g, thus taking him bellow 100kg. As an order of magnitude approximation, is he… • Right in his paranoia, it will take 1g off his scale reading. • Wrong, the force of the moon has no effect on Earth. • Wrong, the force of the moon will have some effect, but not as much as 1g. y • Can’t say, it depends on the position of the Sun, if the Sun were directly overhead too then the combined tidal force of the two would reduce his weight as he says.

11. Solar System Physics 1 • 9. The ideal gas law is PV = NkT. Which of the following statements about it is true? • V = velocity, k = Boltzmann constant, N = number of gas particles. • K = Stefan-Boltzmann constant, V = volume, P = pressure. • V = volume, N = number of particles, k = Boltzmann constant. y • P = density of gas, V = velocity, k = Stefan-Boltzmann constant.

12. Solar System Physics 1 • 10. Planet Vulcan has an atmosphere very similar to that of Earth. What is the maximum Vrms that the particles in the atmosphere can have before this atmosphere is lost? • Vrms > 1/6 Vescape. y • Vrms < 1/6 Vescape. • Vrms > 1/8 Vescape. • Can’t say, need to know mass of Vulcan.

13. Solar System Physics 1 • 11. Putting planetary densities from low to high, which of these lists is correct? • Mercury, Mars, Saturn. • Saturn, Venus, Earth. y • Jupiter, Earth, Venus. • Earth, Venus, Jupiter.

14. Solar System Physics 1 • 12. Which of these statements is true about the Jovian planets? • They have a slower rotation period than the terrestrial planets but a higher surface temperature. • They have a faster rotation period than the terrestrial planets and a higher surface temperature. • They have a slower rotation period than the terrestrial planets and a lower surface temperature. • They have a faster rotation period than the terrestrial planets and a lower surface temperature. y

15. Solar System Physics 1 • 13. Why does the Earth have no atmospheric molecular Hydrogen? • The escape temperature for molecular Hydrogen is too low. Y • The escape temperature for molecular Hydrogen is too high. • Vegetation has converted the Hydrogen into Oxygen via Photosynthesis. • The escape velocity for Hydrogen is too high.

16. Solar System Physics 1 • 14. The escape temperature is directly proportional to μ, and μ has a value of 2 for molecular Hydrogen. Earth has no molecular Hydrogen in its atmosphere, so what must μ be for Nitrogen? • Lower. • Exactly the same. • Not enough information to tell. • Higher. y

17. Solar System Physics 1 • 15. Which pairing of the of the Jovian planets are the most oblate (squashed at the poles) and why? • Jupiter and Saturn, due to their higher masses (than Neptune and Uranus). • Jupiter and Saturn, due to their larger atmospheres compared to their cores. Y • Neptune and Uranus, due to their faster rotation periods. • Neptune and Uranus because they have less dense atmospheres due to their lower masses.

18. Solar System Physics 1 • 16. Think about the internal structures of the Jovian planets. In percentage terms, which of the following is FALSE? • Saturn has a larger upper atmosphere and a smaller lower atmosphere than Jupiter. • Jupiter has the smallest solid core of all the Jovian planets. • Jupiter has the largest upper atmosphere of all the Jovian planets. Y • Uranus and Neptune have a very similar internal structure.

19. Solar System Physics 1 • 17. Which of the Jovian planets have ring systems? • All of them. Y • Saturn and Neptune only. • Saturn only. • Saturn and Uranus only. • Saturn, Neptune and Uranus Only.

20. Solar System Physics 1 • 18. Why did Maxwell conclude that ring systems must be made of ‘an indefinite number of unconnected particles’ i.e. not a solid disk? • Tidal forces would tear a solid disk apart. Y • He calculated their thickness and found that they were not dense enough to be solid. • They did not reflect enough light to be solid. • He showed them to be composed of rock and ice and showed that this combination would not have been able to form a ring system if it were solid.

21. Solar System Physics 1 • 19. The Tardis travels at 4000 m/s when in second gear. If the Doctor flies it through the rings of Saturn orthogonally to the plane of the rings, how long will it take the Doctor to pass through them? Assuming no collisions. • 1 second. • 0.25 seconds. y • 10 seconds. • 0.025 seconds.

22. Solar System Physics 1 • 20. For a moon to be tidally disrupted (as an order of magnitude estimate) it must be the case that, for a point on the moon’s surface… • FG (gravitational force due to moon > FT (tidal force due to planet). • Mmoon > 1/6 Mplanet. • Mmoon < 1/6 Mplanet. • FT > FG. y

23. Solar System Physics 1 • 21. What is the definition of the Roche stability limit? • The distance from a planet’s surface within which tidal forces will break up large objects. • The theoretical maximum width of the band in which moons can sit without being broken up by tidal forces. • The distance from a planet’s centre to the edge of its ring system. • The distance above a planet’s centre below which tidal forces will break up large objects. y

24. Solar System Physics 1 • 22. Which of the following statements about the oceanic tides on Earth due to the Moon is true? • There are two high and low tides every 23 hours. • There is one low and high tide every 23 hours. • There is two low and high tides every 25 hours. y • There is one low and high tide every 25 hours.

25. Solar System Physics 1 • 23. What is the drag force between the Moon and the tidal bulge on Earth causing? • Earth’s days to get longer and the moon to come closer to Earth. • Earth’s days to get shorter and the moon to come closer to Earth. • Earth’s days to get shorter and the moon to move away from Earth. • Earth’s days to get longer and the moon to move away from Earth. y

26. Solar System Physics 1 • 24. Which of the following statements about the oceanic tides on Earth? • Spring tides occur when the Sun and the Moon are aligned on the same side of Earth and neap tides occur when the Moon and the Sun are aligned on opposite sides of Earth. • Spring tides occur when the Sun, Moon and Earth are at right angles to each other and neap tides occur when all three are aligned. • Spring tides occur when the Moon and Sun are aligned on opposite sides of Earth and neap tides occur when the Moon and the Sun are aligned on the same side of Earth. • Spring tides occur when the Sun, Moon and Earth are aligned, neap tides occur when the three are at right angles to each other. y

27. Solar System Physics 1 • 25. What effects do the tidal forces of Jupiter have on its moons, Io and Europa? • Frictional heating on Europa causes continuous volcanic activity but only cracks the icy surface of Io. • The frictional forces may melt the lower portion of Io’s icy surface, thus creating a thin ocean. • Europa has long cracks in its icy surface due to tidal stresses, Io is closer so stresses are more severe, causing serious volcanic activity. Y • Both Io and Europa are close to the break-up limit so are both almost totally molten on the surface due to the frictional heating from tidal forces.

28. Solar System Physics 1 • 26. If the Earth were twice as far from the Sun, and twice as massive, the gravitational force between the Earth and the Sun would be • Half as great as at present. y • Twice as great as at present. • Exactly the same as at present. • Zero.