Homework 3
Due: Thursday, 18th April
Chapter 6 and parts of 7-15
Show your work when required!
b) Where would the Oort cloud lie? (1 mark)
2) Give two reasons why Pluto's classification as a planet should be changed (2 marks)?
3 a) Based on the positions of the planets, which planet would you expect to have the hottest surface temperature?(1 mark)
b) Briefly describe the effect that causes a different planet to actually have the hottest surface temperature. Which planet is this?(3 marks)
4 a) A planet is discovered circling a nearby star just like the sun. Its mass is determined to be 4.6 x 10^{24} kg and its distance from the star is 1.9 x 10^8 km. Would you expect this planet to be terrestrial or Jovian? Give two reasons for your answer. Hint - use the book (2 marks)
b) An object is discovered in our Solar System with an orbit that has a semi-major axis of 12.3 AU, a perihelion distance of 0.5 AU and is inclined at 27 degrees with respect to the ecliptic. Without any further information, would you expect the object to be a asteroid, comet or planet? Justify your answer (there are at least three reasons)(2 marks) .
5 a) (revision of last week). Jupiter lies at a distance of 4.95 AU from the Sun. Calculate it's period in years.(1 mark)
b) Imagine that Jupiter now orbits round a 3M_sun star at the same distance. What would it's period be now? Try and use proportionality. (2 marks)
c) Jupiter's mass is 317 times more than that of the earth. It's radius is 11.21 times that of the Earth. By how much larger is the acceleration due to gravity on Jupiter than it is on the Earth? (2 marks)
d) A `solid bloke' has a mass of 100kg on Earth. What is his mass on Jupiter (1 mark)? Total 20 marks