Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Centripetal force and acceleration problem

  1. Oct 18, 2010 #1
    1. The problem statement, all variables and given/known data
    A 2500 kg car starts from rest and travels along a circular track with a radius of 55.0 meters. The car starts out at a position due East of the center of the track, heading due North initially around the track, which is counterclockwise. The car increases its speed by 105 m/s every minute around the track. How fast is the car traveling when it is 1/4 of the distance around the track? State the car's tangental velocity.


    2. Relevant equations
    v=2*pi*r/period


    3. The attempt at a solution
    I am unsure of how to begin this problem when I'm looking for only 1/4 of the distance. I'm also having a hard time finding the period of one full rotation around the track. Any help would be appreciated! Thanks.
     
  2. jcsd
  3. Oct 18, 2010 #2

    Delphi51

    User Avatar
    Homework Helper

    In this case you are better off doing the magnitude and the direction separately. Figure out the distance for the quarter circle and translate the "105 m/s every minute" into an acceleration in m/s. Then treat it like a linear motion problem and just use your constant acceleration formulas to find the final speed.
     
  4. Oct 18, 2010 #3
    Ok, thank you. Would you mind explaining how I get 105 m/s every minute to m/s for acceleration?
     
  5. Oct 18, 2010 #4
    105m/s per minute translates to an acceleration a = of 105/60 = 1.75 m/sec/sec

    To cover 1/4 th the circumference of a circle of radius is (1/4) * 2 * pi * r

    this gives the distance "S"

    Now use the formula velocity after covering S is =

    V*V = 2* a * S
     
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook