So what if something heavier, like a person, stood on the scale? Would they weigh less when the moon is above them?
If my math is correct LOL
A rough calculation shows that the moon would have about a 0.0003% effect on the weight of an object.
F=(GMoon massSubject mass)/D2
G=6.67x10-11 Moon mass=7.3x1022kg Subject mass=100kg (good for theory) D=distance between moon and subject. The mean distance between the earth and moon is taken to be 3.84x108 meters, although the distance varies a lot, change as appropriate. This distance is between the centers, so to get the effect on someone standing on the earth's surface, subtract 6.4x106meters from that, leaving 3.78x108 meters between the center of the moon and a person on earth.
(6.67x10-11 x 7.3x1022 x 100)/ ( (3.78x108)2 ) = 0.0034Newtons, which would be the equivalent of 0.35 grams
This means a 100kg person would see about 0.3 to 0.4 grams of change due to the moon. Which is why the sensitivity of the scale needs to be very high. Measuring over a full rotation of earth should give a variability in the weight of about double, meaning close to 0.7 or 0.8g. The scale would have to measure 100.0000kg to show these changes. It would go from 100.0003kg to 99.9997kg over the max and min readings.
The moon gets closer and farther than the mean distance, so additional calculations can be done to get more accurate readings.
Yes.
If you could measure down to 0.001 pounds and stood there, without respiration, food, or sweating for the experiment.
Another option would be to get a very large scale, - the more sensitive the better - and find something very close to max weight there too.
Think a 2 ton scale that might go down to 0.1 or even 0.01 pounds, and putting just under 2 tons on it.
I have no idea if such things exist or how much they would cost, but it would be a lot. A big balloon of water suspended on a tree might work on a still day, but any variables such as wind or animals might cause weird readings.
I don't know what could be done with standard household equipment.
Load cells are pretty good devices. they convert forces (loads) into electrical signals which can then be measured. This is how all digital scales work.
The key to a good load cell measurement is to get the proper range, and sensitivity, along with electronic conditioning (amplification and filtering) to make the output workable for your situation.
People are notoriously bad experiment subjects as everything we do - including movement - typically affects the readings. Better to use a solid object on a "step on" scale, and anything that can be done with suspension is usually good with water, since it is readily available and relatively heavy.
I might do the calculations to see how much of an impact the moon has on weight, but I don't suspect it is much on the whole.
I just find it weird that gravity from the moon pulls on the oceans, but nothing else. Everything else is microscopic in change and has a huge margin of error. But we can see massive bodies of water go up and down because of the "moon's gravity". Nothing else.
Typically, big things aren't easy to visualize.
The tides are a slow moving effect, with 0.0003% of the ocean mass rising up. But that 0.0003% becomes huge when dealing with a huge ocean.
my 0.0003% of $100 is tiny, but when looking at a trillion dollars, that becomes enough to do a lot with.
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