1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Terminal Speed

  1. Oct 2, 2004 #1
    What is the terminal speed of a 6.5 kg spherical ball with a radius of 3.0 cm and a drag coefficient of 1.50? The density of the air through which the ball falls is 1.2 kg/m3.

    I used vt=sqrt((2Fg)/(CpA)). Where Fg is force of gravity, C is drag coeff., p is air density , and A is cross sectional area. When I plug in the numbers I get the wrong answer. I used 1.5 as C, 1.2 as p, 9.8 as Fg, and (9*pi) as a (area of circle-pi*r^2). What am I doing wrong.
     
  2. jcsd
  3. Oct 2, 2004 #2
    I think you need to convert your radius to meters.
     
  4. Oct 2, 2004 #3
    I forgot to convert lol but that doesn't help, answer is still wrong.
     
  5. Oct 2, 2004 #4
    Never Mind Figured it Out :)
     
  6. Oct 2, 2004 #5

    Clausius2

    User Avatar
    Science Advisor
    Gold Member

    Your expression hasn't got units of velocity.

    I think you have forgotten to include the sphere mass in Fg.
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?



Similar Discussions: Terminal Speed
  1. Terminal speed (Replies: 6)

  2. Terminal Speed (Replies: 1)

  3. Terminal Speed (Replies: 2)

Loading...