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Homework Help: Finding missing components given speed and direction.

  1. Jul 19, 2011 #1
    1. The problem statement, all variables and given/known data
    #26 (on attachment). The speed of an object and the direction in which it moves constitute a vector quantity known as the velocity. An ostrich is running at a speed of 17.0 m/s in a direction of 68 degrees NW. What is the magnitude of the ostrich's velocity component that is directed (a) due north and (b) due west?

    2. Relevant equations
    R2 = A2 + B2 – 2ABcosθ
    x: (hyp)(cosθ)
    y: (hyp)(sinθ)

    3. The attempt at a solution
    I have no idea what do to. This is my summer assignment for ap physics and ive not taken pre-cal or cal or physics before so im confused. i have a couple more problems like this that im confused in, but thats a different thread..

    Attached Files:

  2. jcsd
  3. Jul 19, 2011 #2
    This uses right triangle trig. If you plot the velocity vector of the ostrich on a graph, starting at the origin, can you figure out where it will end? You know the hypotenuse and you're looking for the x- and y-components.
  4. Jul 19, 2011 #3
    ohh. now i feel stupid that i didn't think of that before.
  5. Jul 19, 2011 #4
    should i round to nearest tenth or hundredth?
  6. Jul 20, 2011 #5
    tenth will be ok
  7. Aug 17, 2011 #6
    so would the units be m/s or not since it asks for magnitude??
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