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Homework Help: Weigh something with multiple scales

  1. Dec 19, 2008 #1
    First off I'm not in school and therefore my question isn't for homework. This is more of a question as to whether something is possible based on physics. However, I think the course-work section is the best spot for this.

    1. The problem statement, all variables and given/known data

    Is it possible to weigh a standard wooden pallet 40inX48in using 4 bathroom scales at the 4 corners?

    Max weight of pallet with boxes: 750lbs
    Max measurable weight of bathroom scales: 300lbs

    Weight of boxes on pallet is evenly distributed
    Weight of pallet with boxes is evenly distributed across the 4 scales

    1. Is this even possible or will the scales simply be crushed?
    2. If it is possible, and I gather 4 weights, from the 4 scales, at 4 corners, do I add the weights together or average them? Or is the calculation more complicated than this?

    2. Relevant equations

    3. The attempt at a solution

    1. The problem statement, all variables and given/known data

    2. Relevant equations

    3. The attempt at a solution
  2. jcsd
  3. Dec 19, 2008 #2
    Hey, borrow your neighbour's scales, get into your bathroom and stand one foot on each pair of scales. Physics is about experiments!
  4. Dec 19, 2008 #3
    The total force downwards (the weight of the pallet), must be reacted by a total and equal opposite reaction force (from the scales).

    if you spread the weight exactly evenly over the four scales, you would measure the total mass of the pallet over all the scales. In other words, you would have to add the masses that you read on the scales to get the total mass.

    you'll have to:
    position the scales very well on a flat surface
    lower the pallet onto all four evenly and at the same time
    make sure the guage part is sticking out so that you can read the measurements :wink:

    Take some photos and let us know how it goes.
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