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Homework Help: Constant acceleration problem

  1. Sep 19, 2005 #1
    A 3.7 kg penguin runs onto a huge sheet of frictionless Anarctic ice. At t=0 is is at x=0 and y=0 with an initial velocity of 0.41 m/s along the positive x-axis. It slides while being pushed by the wind with a force of 0.29 N directed along the positive y-axis. Calculate the magnitude of the penguin's velocity at t= 9.26 s.

    I started this problem by first using Newton's 2nd Law to calculate the acceleration.
    F=ma
    .29 N= 3.7a
    a= .0784 m/s^2

    Then I used the equation v=v initial + at
    v= .41 + .0784(9.26)
    and got 1.14 m/s.

    This wasn't right, can someone tell me what I'm doing wrong?

    thanks in advance
     
  2. jcsd
  3. Sep 19, 2005 #2

    Doc Al

    User Avatar

    Staff: Mentor

    This is the acceleration in the y-direction.

    You are mixing up x and y components. (The .41 is the x-component of the velocity, which remains constant.)

    The initial speed in the y-direction is 0. Calculate the x and y components of the velocity separately, then combine them.
     
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