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A Question of Weight

  1. Nov 6, 2015 #1
    Its the age old question which weighs more, a ton Styrofoam Balls a 1/4" in diameter or a ton of Steel Balls a 1/4" in diameter?

    Of course the answer is that both weigh the same.

    Now seeing as both weigh the same which would cause more harm to you if you stood underneath of them and let them drop on you from a height of 20 feet in the air?

    The steel balls would of course because the Styrofoam Balls falling from 20 feet would be influenced by the air thus causing some of the Styrofoam Balls to not land on you. So is the age old answer to the question of, is a ton of Styrofoam Balls the same weight as a ton of Steel Balls being yes still a valid answer?
  2. jcsd
  3. Nov 6, 2015 #2

    Buzz Bloom

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    Gold Member

    Hi Dryson:

    I don't get why you think the added context off falling would possibly affect the answer to the question. Can you elaborate on that?

    Do you have in mind that the concept of "weight" changes when an object falls?

    BTW, even if you were on the moon (in a space suit), the Styrofoam would do less damage even though the momentum when the each of balls hits your head would be the same.

  4. Nov 6, 2015 #3


    Staff: Mentor

    The age-old question as I heard it, was "Which is heaver, a pound of silver or a pound of lead?"
    The answer to this question is "a pound of lead."

    The reason is that silver, gold, and precious stones are measured in Troy units (troy lb and troy oz), while other materials are measured in avoirdupois units. See https://en.wikipedia.org/wiki/Troy_weight
    1 troy pound ##\approx## 373.24 g.
    1 avoirdupois pound ##\approx## 454 g.
  5. Nov 6, 2015 #4


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    Science Advisor

    I doubt that "which weighs more, a ton Styrofoam Balls a 1/4" in diameter or a ton of Steel Balls a 1/4" in diameter?" really is an "age old" question since Styrofoam is not itself "age old"!

    I don't see what the fact that the steel balls hurting more than the Styrofoam balls has to do with the question of its weight so I don't understand your question.
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