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!

Circular Motion of mass

  1. Mar 14, 2006 #1
    bucket of mass 1.80 kg is whirled in a vertical circle of radius 1.10 m. At the lowest point of its motion the tension in the rope supporting the bucket is 25.0 N.
    Find the speed of the bucket.

    f(t)-mg=mA

    25-17.64=1.8 A
    7.36 = 1. 8 A
    A= 4.08

    I'm told the answer above is incorrect, and someone point out my mistake?
     
  2. jcsd
  3. Mar 14, 2006 #2

    nrqed

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    They are asking for the speed . You found the centripetal *acceleration*. You know how the two are related in circular motion?
     
  4. Mar 14, 2006 #3
    acceleration is velocity squared over time

    Speed would be 2 pi radius over time

    4.08= v^2/1.10
    4.08/1.1 = 3.71
    Square root of 3.71 = 1.93

    Would 1.93 then be the speed?
     
  5. Mar 14, 2006 #4

    nrqed

    User Avatar
    Science Advisor
    Homework Helper
    Gold Member

    no! (over the radius! Not the time!)

    I don't see how this help syou since you don't have the time...But it's true, if by "time" you mean the time for one rotation, the period.

    Check you algebra!!
     
Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?