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: Mechanics with vectors question!

  1. Mar 30, 2010 #1
    Alright all ive been attempting this question and ive become stuck.

    This is the question.

    1. The problem statement, all variables and given/known data

    http://img707.imageshack.us/img707/2575/63353658.jpg [Broken]

    2. Relevant equations

    In the working out.

    3. The attempt at a solution

    So for the first part i wrote F=Mx^.. (X double dot).
    I also stated that if there was no force acting on the particle then the particle would stay at a constant speed V if we ignored instances such as the particle being on a slope.

    For the second part i wrote (Im using X to denote x hat (x^^), same applied with y.)

    F_x X + F_y Y = m x^.. X + m y^.. Y

    => x^.. = 2 , y^.. = 3x^2

    Now for the third part when writing down the inital conditions this is where i become confused. Shall i write it in plain english such as;

    At time equal to 0, this displacement of the particle x^.. will be 0.

    Im not too sure how to answer that part, or the last part.

    Any help is greatly appricated cheers people :)
    Last edited by a moderator: May 4, 2017
  2. jcsd
  3. Mar 30, 2010 #2
    For the trajectory eqn. you can integrate the two eqn. you got in the previous part twice w.r.t time . Then eliminate the t from the two eqn. to obtain the relationship b/w x and y.
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook