Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Exam Problem: Rounds per minute into Megabits per second

  1. Jul 20, 2005 #1
    Hi, guys! :approve:
    My exam comes in one week, so I need your urgent help :cry:
    I found out, that one of the problems in the exam will be about convertion between rounds per minute (of a CD or HDD) and megabits per second (as reading speed). I have no idea what is the dependance between those two measures. :confused: Does anyone of you know a formula for convertion or have any clues how to derive such a formula.... Help?!
    Greatly appreciate your concern :smile:
  2. jcsd
  3. Jul 21, 2005 #2
    You would need to find out how many megabits can be read in one revolution. Then it should be pretty easy, but without that information, I have a feeling this problem is impossible.
  4. Jul 21, 2005 #3
    OK, if the question asks about how many megabits are read in one revolution, you say that "it should be pretty easy". Still, it is very foggy for me :-). Perhaps you could provide a small tip? ;)
  5. Jul 21, 2005 #4


    User Avatar
    Science Advisor

    No, that's not what he said. he said you need to know how many bits can be read in one revolution. I presume that by "rounds per minute" you mean "revolutions per minute". Multiply that by "bytes read per revolution".
  6. Jul 21, 2005 #5
    Hehe... nice point of view! :rofl:
    However, this, being an exam problem, is assumed to be a little bit more complicated than simple arithmetics. :rolleyes:
    I think it is enough to know the radius, the angular velocity (or frequency) and the time to read one bit (or distance b/n bits)... Once having these variables, how should I combine the megabits and the revolutions?! :confused: This is my problem
    Thanks for your answers :shy:
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook