1. Limited time only! Sign up for a free 30min personal 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!

Volume of cylinders

  1. Sep 15, 2011 #1
    which is greater or are they equal: one cylinder with 2 radius and height 10, or one with 1 radius and height 20

    I thought they would be equal because the first one is

    4pi * 10 = 40pi

    and the second is

    2pi * 20 = 40pi

    But my book says the first is greater. don't understand why
     
  2. jcsd
  3. Sep 15, 2011 #2

    pwsnafu

    User Avatar
    Science Advisor

    Start again. What's the formula for volume of a cylinder?
     
  4. Sep 15, 2011 #3
    ok, pir^2h not pi(2r)h

    now i get it
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook