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!

Forces and rotational motion

  1. Nov 19, 2013 #1
    1. The problem statement, all variables and given/known data

    This question is about forces and rotational motion.
    (a) Figure 1.1 illustrates a force of 180 N acting at a perpendicular distance of 0.40 m from a point O. Calculate the torque about O.

    (b) Figure 1.2 illustrates a circular drum of radius 0.080 m around which a rope is wound. The drum is turned by means of a handle of length 0.40 m to which a force of 180 N is applied at right angles to the handle.
    Calculate the tension T in the rope.

    (c) A person is pulling a boat on to a trailer using the drum system from (b), known as a winch, as shown in Figure 1.3. The person is exerting a force of 180 N on the handle.
    Calculate the force which the trailer exerts on the axle of the winch when the handle is in the position shown in Figure 1.3.

    2. Relevant equation
    Torque=Force×distance

    3. The attempt at a solution

    (a) Torque=Fr=180(0.4)=72Nm
    (b) ƩT=0
    0.08T-180(0.4)=0
    T=180(0.4)/0.08=900 Nm
     

    Attached Files:

    • 1.PNG
      1.PNG
      File size:
      4 KB
      Views:
      79
    • 2.PNG
      2.PNG
      File size:
      4.7 KB
      Views:
      76
    • 3.PNG
      3.PNG
      File size:
      49 KB
      Views:
      76
  2. jcsd
  3. Nov 19, 2013 #2

    haruspex

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member
    2016 Award

    Your a) and b) answers are right. What's your thinking on c)?
     
  4. Nov 19, 2013 #3
    i am trying to figure out the free body diagram for part c
     
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: Forces and rotational motion
Loading...