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Train ride relative motion

  1. Jan 22, 2013 #1
    You are on a train traveling east at speed of 14.0 m/s with respect to the ground.

    if you walk west toward the back of the train, with a speed of 1.4 m/s with respect to the train, what is your velocity with respect to the ground?

    I got the answer as 12.6 m/s east but is my answer going to be positive or negative
  2. jcsd
  3. Jan 22, 2013 #2

    Doc Al

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    Staff: Mentor

    12.6 m/s east is correct. If you said negative 12.6 m/s east, that would mean it was going to the west, which is not correct.

    You're giving a magnitude (which is always positive) and a direction.
  4. Jan 22, 2013 #3


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    That depends on which direction is positive and which negative.
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