Quote:
Originally Posted by javadog
Actually, it weighs more when closer to the center of the earth.
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If in space, then sure. But only because the the masses are coming closer. But as soon as there is building mass on the side opposite the center... well, consider how the moon and sun's gravitational fields distorts the earth.
https://www.thoughtco.com/land-tides-or-earth-tides-1435299
Or imagine a planet of 100% water, with the block of steel at the center. What would be the big gravitational force on that block of steel, and which way would this gravitational field accelerate that block?
Quote:
Originally Posted by javadog
That weight doesn’t change, the buoyant force just opposes it.
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Smart ass!
Of course saying that
weight doesn't change leaves ambiguity about the weight measured. I mean, if you jump on a trampoline, are you not weightless in the air? There are no forces holding you in the air. You posses both mass and acceleration yet for a moment you are weightless - just as you would be in space.
Back to the ocean thing... If, as an engineering exercise, the questions arose of,
how much force would be needed to suspend a 100_lb ingot of Aluminum in a freshwater lake?
would you answer 100_lbs ? Yeah, you probably would. -LOL
But would you show your work...
SGAl = 2.6,
Suspension Force = 100-(100/2.6)= 61.54_lbf
Buoyancy Force = 100/2.6 = 38.46_lbf
Total Force = Buoyancy Force + Suspension Force = 100_lbf
Or would you leave those details of the answer hanging until your teacher marked "100_lbf" wrong?
Not that I would ever do anything like that. 