joe windsurf said..a bucket full of water weighs more than the same bucket full of crap
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Just on a technical point,.. a bucket of excrement weighs almost the same as a bucket of water.
The proof of this is that when you drop a big steaming darky in the pan, some float and some sink.
Now,.. the ones that float support your hypothesis, but the ones that sink, negate your hypothesis.
So,.. given that sometimes they float and sometimes they sink, that sort of indicates they must on average, be very close to neutral buoyancy, and therefore of a similar weight when measured by the bucketful.
(Although I'm not familiar with the situation in canada. Perhaps next time you drop a few you can give us an update.
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Also,.. air pressure make no difference and can be as low as zero if you like.
Up a mountain makes no difference either, neither does being in a big hole.
I think water temperature makes no difference so long as the water you put in the bucket is the same temperature as the water which the board is floating in.
It's all about a board floating in water displacing the exact same weight of water as the board weighs.
That's not my idea. Archimedes thought of it first.
In any case, experimental error would be much greater than the small difference in density between different temps of water would make, so I wouldn't be too fussed about it.
Oh,.. and you don't have to lift the 160kg of water in the bucket off the board and onto the scales.
NotWal's devilishly cunning plan is to mark the level of the water in the bucket and then just tip it into the pool.
Take the bucket out of the pool (empty of course,,.. the bucket,, not the pool,.. and I'm being very specific here so as not to cause any confusion,.. and then,... now where was I,?.. oh yes,..
measure water level in bucket, empty bucket in pool, remove bucket from pool, put empty bucket on bathroom scales and then,,... refill to the marked level and read bathroom scales.
Your 160 litre bucket and water should read about 146 kg, and your board should weigh about 14kg to give you a grand total of 160kg total weight, which translates to 160 litres.
If it comes out to 140 kg total you were sold the wrong board because that would be a 140 liter board.
If it comes out to 79kg, you probably picked up the wrong board, and it's not even yours.
Also,.. not only but also,.. I was thinking about how the lizard people could do this on the moon, or Pluto,.. given that gravity is so much less there.
I have a feeling that it would still work so long as they don't use the bathroom scales but instead use one of those old railway beam balance measuring scales.
Bathroom scales balance a gravitational force with a spring force and that would definitely give a wrong reading. But, railway balance scales balance a gravitational force with a gravitational force, so whatever the gravity is, the two would balance out. Thus, 160 kg of water and bucket would still weigh in at 160 kg apparent weight, even if gravity was only 10% of earth gravity.
Soooo,.. my impression is that this method would still work because although the weight of the bucket would obviously be much less, the balance weight on the balance beam would also be much less even though it be marked with a 160 kg marking. Therefore, so long as you took notice of what the balance weights were marked, it should still give you the right answer.
The only time this would not work is when there was no gravity at all,.. I think,..
This is frightfully good news to all because I'm sure we're right on the verge of an era when all this will prove very useful, or not,.. as the case may be.
I'm prepared to be proven wrong on this point but so far I can't think why it would be.
Maybe NotWal can think of a reason, since it's his idea.
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