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Closest poing of approach

  1. Oct 13, 2010 #1
    1. The problem statement, all variables and given/known data
    Two objects 1 and 2 are moving towards each other, 1 along the x axis and the 2 along the y axis. Initially, object 1 is at (- 28.9,0) (in m) moving at speed v 1 = 13.7 m/s, while 2 is at (0.-36.8) (in m) moving at speed v 2 = 7.5 m/s. How long does it take untill the objects are at the minimum distance from each other? (give your answer in s)

    2. Relevant equations
    I just don't know where to start from... like all i need is a hit or formula. I have no clue how to find the closest poing of approach.

    3. The attempt at a solution

    *Btw i am new to the forum and this is the first time i am posting something. So, if i make any errors, kindly tell me.

  2. jcsd
  3. Oct 13, 2010 #2
    write the equation of motion for each partile, i.e. x0+v1t, etc.
    and use the distance equation sqrt(x^2 + y^2). then...
  4. Oct 15, 2010 #3
    Thank you very much. I figured it out...and then you differentiate it and put it equal to 0 and solve for t...Thanks ;-)
  5. Oct 15, 2010 #4
    You're very welcome, Nikieme
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