Physics 3333 / CFB 3333 Homework 4

Based on the video "In Search of the Edge".

Non-honors CFB 3333

  1. Research these four flat-earthers. Are they real people? Find out all you can about them. Cite your sources.
  2. Come up with your own proofs that the Earth is round. They should be simple enough for a child to understand and still be convincing. The proofs can be based on common experience, or they can entail a simple, inexpensive experiment which you must describe in sufficient detail actually to be carried out.

    If the video addressed your proof, explain why the video is mistaken. For example, if you say, "Look at a picture of the Earth taken from space. It looks round," remember that Vanderkuur explained in the film that gravity bends light and makes straight things appear curved. You then need to explain the error in Vanderkuur's argument.

PHYS 3333 and Honors CFB 3333

  1. The university professor, Leo Ferrari, claims that one cannot feel the Earth moving although the equatorial speed is 1000 miles/hour. He then says that a merry-go-round travelling at 10 miles/hour makes one dizzy.
    1. Calculate the centripetal acceleration for the spinning Earth in m/s2 and in "g"s (Earth gravities).
    2. Calculate the centripetal acceleration for the merry-go-round in m/s2 and in "g"s.
    3. How much larger is the merry-go-round effect?
    4. Even if Earth rotated much, much faster, you still would not get dizzy, but on the merry-go-round you do. What is the reason for this? (Think about your senses and psychology.)
  2. Scientist George Vanderkuur claims that buildings are wider at the top than at the bottom because they are built using plumb bobs which point toward the center of the supposedly round Earth.
    1. Research the dimensions of the tallest unit of the Sears Tower.
    2. In theory, how much wider is the top than the bottom, in millimeters?
    3. What percentage of the building width is this?
    4. To what tolerances are real skyscrapers constructed? Cite your source of information.
  3. How far is a horizontal light beam bent vertically after traveling 10 miles in the Earth's gravitational field?
  4. If you were in the middle of the very calm Pacific Ocean perched atop the 16-foot tall mast of a ship, how distant is your horizon?

Bonus

Work through as much of the other class' assignment as you can.

Hand in the assignment on paper, send it to pseudo@physics.smu.edu, or turn in a disk or CD.