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!

Homework Help: Rock on a string

  1. Mar 19, 2012 #1
    1. The problem statement, all variables and given/known data
    so theres a 6 kg rock spinning in a circle with a string that can with stand a maximum tension of 75 and a radius of 1.5m
    and i need to find the maximum speed before the string will break


    2. Relevant equations

    Fnet=ma
    a=4[itex]\pi[/itex]2R/T2

    3. The attempt at a solution
    so Fnet =ma and a = 4[itex]\pi[/itex]2R/T2
    so Fg = m*4[itex]\pi[/itex]2R/T2
    so 6*9.8 = 6*4[itex]\pi[/itex]21.5/T2
    so 58.8 = 284.24 / T2
    so T = 2.2

    no would i be able to use this formula a=4[itex]\pi[/itex]2R/T2 to find the acceleration and then use a= v2/R to get the speed?
     
    Last edited: Mar 19, 2012
  2. jcsd
  3. Mar 19, 2012 #2
  4. Mar 20, 2012 #3
    no nothing?
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook