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Spring Scales Mass Force

  1. Dec 3, 2009 #1
    Spring Scales Mass Force !!!!

    1. The problem statement, all variables and given/known data
    This is 2 questions.

    1.A student hangs a 500.0g mass on a spring scale. Correct two significant digits, state the reading on the scale when the the mass and the scale are

    (a) Stationary
    (B) Being Lifted Upward at constant velocity
    (c)realesed so they fall downward freely

    2. A student 65kg can safetly lift 73% of the students own mass off the floor?
    (a) Determine the mass the student can lift on earth

    2. Relevant equations


    3. The attempt at a solution

    First Question the stationary I put

    Fg= mg
    Fg= 4.9N
  2. jcsd
  3. Dec 3, 2009 #2
    Re: Spring Scales Mass Force !!!!

    Question seems to simply be (65kg)(0.73) since mass is independent of gravity or what planet one is on.
  4. Dec 3, 2009 #3
    Re: Spring Scales Mass Force !!!!

    Well... For part B, if it's moving at a constant velocity (as opposed to a constant acceleration), shouldn't make a difference, right?

    I mean, if something is moving at a constant velocity, then that means there are no net forces acting on it. And that would mean that the only force actually acting on the weight and scale would be gravity itself.
  5. Dec 3, 2009 #4
    Re: Spring Scales Mass Force !!!!

    thanks guys
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