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Homework Help: Acceleration, magnitude, displacement.

  1. Oct 7, 2007 #1
    1. The problem statement, all variables and given/known data
    a spaceship is observed traveling in the positive x direction with a speed of 150m/s when it begins accelerating at a constant rate. the spaceship is observed 25s later traveling with an instantaneous velocity 1500m/s at an angle of 55 degrees above the x+ axis. a.) calculate the acceleration of the spaceship in the x direction, Ax, and in the y direction, Ay, during 25 seconds. what was the magnitude of the spaceship's acceleration during the 25 seconds? b.) what was the magnitude of the displacement of the spaceship after 25 seconds?

    2. Relevant equations
    a= delta v/ delta t

    X= 1/2(Vo+V)t

    3. The attempt at a solution

    for part a i attempted it but i didnt get anything right:

    cos55((150m/s)/(150 m/s)) = .0574 in positive x direction.
    sin55((150m/s)/(150 m/s)) = .0819 in positive y direction.

    a= delta v/delta t
    1500-150/25-0 = 1350/25 = 54 m/s^2

    magnitude: 1500^2/150^2 =150^2/150^2 +b^2
    = sq. root of 2250000-22500 = b
    b= 1492 m/s

    part b)
    X= 1/2 (Vo+V)t
    X= 20625 m/s^2 in positive x direction.
  2. jcsd
  3. Oct 7, 2007 #2
    please help me out with this. i want to know what i did wrong.
  4. Oct 7, 2007 #3
    i was thinking for the acceleration part, maybe i am supposed to switch the values? so it would be 150-1500/0-25?
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