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: Force Problems

  1. Oct 18, 2007 #1
    I'm having a lot of trouble solving force problems even though I understand the concepts (or, at least I think I do). This is a specific example:

    A sphere of mass 3.0 x E-4 kg is suspended from a cord. A steady horizontal breeze pushes the sphere so that the cord makes an angle of 34 degrees with the vertical when at rest.

    Find the a) magnitude of that push and b) the tension in the cord.

    The only equation that I know of to solve force problems is F=ma. We have m.

    I think that I can use trig to find F, but I can't figure out how.
    I tried to solve for F by using components: I found the downward force by finding mg (= -2.94 E-3). I'm kind of stuck now. Any suggestions?
    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Oct 18, 2007 #2


    User Avatar
    Homework Helper

    Divide the tension in the cord into 2 compoennts... horizontal and vertical. If T is the tension, what is the horizontal component of tension? what is the vertical component of tension?

    net force in x direction = max... however ax = 0

    net force in the x direction = 0

    same way

    net force in the y direction = 0

    What are the forces acting vertically... what are the forces acting horizontally?
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook