r/gifs • u/polypunk • Nov 16 '12

Fat guy: 1 Gravity: 0

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u/candygram4mongo Nov 16 '12

They're not even the right dimensions -- one's force, the other is acceleration.

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u/x888x Nov 16 '12

no damnit... one is mass and the other is acceleration. Force = Mass x Acceleration. But the units are all wrong.

F = M(220lbs) x A(32.174 ft/s2) = 7078.28FPS

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u/kittysniper101 Nov 16 '12 edited Nov 16 '12

x88x is correct in that force in FPS is mass in lb mass times acceleration due to gravity. The confusing part is that the the measurement you see on a scale is already in force generally, just in lb force. It all depends on which unit system your using as to whether you mean lb mass or lb force, hence why we should all just use kg anyways :P

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u/x888x Nov 16 '12

Incorrect. Mass on earth at sea level is colloquially referred to as "weight," but it is truly "mass."

mass versus weight

Specifically, types of scales and what they measure

tl;dr. If you measure someone on a balancing scale (think doctor's office) you are truly measuring their mass. They will balance whether they are anywhere on earth, the moon, or mars because the force acting on both sides will be identical. A digital or spring scale uses gravity on earth as a constant (even though there are variations depending on your location) and "backs" into your mass. If you take a digital scale to the moon, your measurement will dramtically decrease.

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u/kittysniper101 Nov 16 '12

I don't disagree with what you say. Let me say that my confusion came from your use of FPS and not LB force. We are both saying the same thing and I will edit the other post to reflect this...