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!

Torque Help -- Tension in a Hoist Cable

  1. Jan 11, 2015 #1
    Hi, I'm having a problem with 3. (b) (ii) here.

    I know that the frictional torque is 1500Nm and that from (b)(i) being 5055N I assume this is multiplied by 1.5M (drum shaft radius) which gives me 7582.5N. Do I have to calculate the angular acceleration of the drum from here, which could then give me the torque? And if so, how?

    Help much appreciated. Answer and solution below.

    9fVTB.jpg
    1dUdy.jpg
     
  2. jcsd
  3. Jan 11, 2015 #2
    In addition to this how is the power calculated for (b)(iii)? I understand it is two times the torque but why?

    Thanks.
     
  4. Jan 12, 2015 #3

    CWatters

    User Avatar
    Science Advisor
    Homework Helper

    Two times the torque?

    Power = Torque * angular velocity
     
  5. Jan 12, 2015 #4

    CWatters

    User Avatar
    Science Advisor
    Homework Helper

    Yes.

    First calculate the angular acceleration from the velocity of the rope and the dimensions of the drum.

    Then what equation relates torque and angular velocity?
     
    Last edited: Jan 12, 2015
  6. Jan 12, 2015 #5

    CWatters

    User Avatar
    Science Advisor
    Homework Helper

    PS: The Torque will not be the value calculated earlier because part iii) says "at a constant speed".
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?
Draft saved Draft deleted



Similar Discussions: Torque Help -- Tension in a Hoist Cable
  1. Patient hoist (Replies: 5)

Loading...