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Homework Help: Velocity x component

  1. Sep 17, 2011 #1
    1. The problem statement, all variables and given/known data
    A jetliner is moving at a speed of 233 m/s. The vertical component of the plane's velocity is 66.9 m/s. Determine the magnitude of the horizontal component of the plane's velocity.

    3. The attempt at a solution
    66m/s cos(90)=0

    I am not really sure how to find velocity from speed without knowing the angle... It's not given that it is 90... I know this is supposed to be easy but I am a beginner.

    Thanks for help
  2. jcsd
  3. Sep 17, 2011 #2

    You are almost there:
    So its Vx=Vcos(theta)

    So then with algebra its: arccosine(Vx/V)=theta....plug in your given numbers..
    Theta = 73.3 degrees

    Then find the y component with Vy=Vsin(73.3) = 233sin(73.3)=223 so Vy=223m/s

    to check this then you would do sqrt(Vx^2+Vy^2)=V
    Last edited: Sep 17, 2011
  4. Sep 17, 2011 #3
    Beat me to it. But yeah do this.
  5. Sep 23, 2011 #4
    Thanks!!! That was helpful!
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