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But unlike most people it understands that even though an ounce of gold weighs more than an ounce of feathers a pound of gold weighs less than a pound of feathers.

(To be fair this is partly an obscure knowledge question, the kind of thing that maybe we should expect GPT to be good at.)




That's lame.

Ounces are an ambiguous unit, and most people don't use them for volume, they use them for weight.


None of this is about volume. ChatGPT: "An ounce of gold weighs more than an ounce of feathers because they are measured using different systems of measurement. Gold is usually weighed using the troy system, which is different from the system used for measuring feathers."


Are you using Troy ounces?


The Troy weights (ounces and pounds) are commonly used for gold without specifying.

In that system, the ounce is heavier, but the pound is 12 ounces, not 16.


>even though an ounce of gold weighs more than an ounce of feathers

Can you expand on this?


Gold uses Troy weights unless otherwise specified, while feathers use the normal system. The Troy ounce is heavier than the normal ounce, but the Troy pound is 12 Troy ounces, not 16.

Also, the Troy weights are a measure of mass, I think, not actual weight, so if you went to the moon, an ounce of gold would be lighter than an ounce of feathers.


Huh, I didn't know that.

...gold having its own measurement system is really silly.


Every traded object had its own measurement system: it pretty much summarizes the difference between Imperial measures and US Customary measures.


> Every traded object had its own measurement system

In US commodities it kind of still does: they're measured in "bushels" but it's now a unit of weight. And it's a different weight for each commodity based on the historical volume. http://webserver.rilin.state.ri.us/Statutes/TITLE47/47-4/47-...

The legal weights of certain commodities in the state of Rhode Island shall be as follows:

(1) A bushel of apples shall weigh forty-eight pounds (48 lbs.).

(2) A bushel of apples, dried, shall weigh twenty-five pounds (25 lbs.).

(3) A bushel of apple seed shall weigh forty pounds (40 lbs.).

(4) A bushel of barley shall weigh forty-eight pounds (48 lbs.).

(5) A bushel of beans shall weigh sixty pounds (60 lbs.).

(6) A bushel of beans, castor, shall weigh forty-six pounds (46 lbs.).

(7) A bushel of beets shall weigh fifty pounds (50 lbs.).

(8) A bushel of bran shall weigh twenty pounds (20 lbs.).

(9) A bushel of buckwheat shall weigh forty-eight pounds (48 lbs.).

(10) A bushel of carrots shall weigh fifty pounds (50 lbs.).

(11) A bushel of charcoal shall weigh twenty pounds (20 lbs.).

(12) A bushel of clover seed shall weigh sixty pounds (60 lbs.).

(13) A bushel of coal shall weigh eighty pounds (80 lbs.).

(14) A bushel of coke shall weigh forty pounds (40 lbs.).

(15) A bushel of corn, shelled, shall weigh fifty-six pounds (56 lbs.).

(16) A bushel of corn, in the ear, shall weigh seventy pounds (70 lbs.).

(17) A bushel of corn meal shall weigh fifty pounds (50 lbs.).

(18) A bushel of cotton seed, upland, shall weigh thirty pounds (30 lbs.).

(19) A bushel of cotton seed, Sea Island, shall weigh forty-four pounds (44 lbs.).

(20) A bushel of flax seed shall weigh fifty-six pounds (56 lbs.).

(21) A bushel of hemp shall weigh forty-four pounds (44 lbs.).

(22) A bushel of Hungarian seed shall weigh fifty pounds (50 lbs.).

(23) A bushel of lime shall weigh seventy pounds (70 lbs.).

(24) A bushel of malt shall weigh thirty-eight pounds (38 lbs.).

(25) A bushel of millet seed shall weigh fifty pounds (50 lbs.).

(26) A bushel of oats shall weigh thirty-two pounds (32 lbs.).

(27) A bushel of onions shall weigh fifty pounds (50 lbs.).

(28) A bushel of parsnips shall weigh fifty pounds (50 lbs.).

(29) A bushel of peaches shall weigh forty-eight pounds (48 lbs.).

(30) A bushel of peaches, dried, shall weigh thirty-three pounds (33 lbs.).

(31) A bushel of peas shall weigh sixty pounds (60 lbs.).

(32) A bushel of peas, split, shall weigh sixty pounds (60 lbs.).

(33) A bushel of potatoes shall weigh sixty pounds (60 lbs.).

(34) A bushel of potatoes, sweet, shall weigh fifty-four pounds (54 lbs.).

(35) A bushel of rye shall weigh fifty-six pounds (56 lbs.).

(36) A bushel of rye meal shall weigh fifty pounds (50 lbs.).

(37) A bushel of salt, fine, shall weigh fifty pounds (50 lbs.).

(38) A bushel of salt, coarse, shall weigh seventy pounds (70 lbs.).

(39) A bushel of timothy seed shall weigh forty-five pounds (45 lbs.).

(40) A bushel of shorts shall weigh twenty pounds (20 lbs.).

(41) A bushel of tomatoes shall weigh fifty-six pounds (56 lbs.).

(42) A bushel of turnips shall weigh fifty pounds (50 lbs.).

(43) A bushel of wheat shall weigh sixty pounds (60 lbs.).


Why are you being downed!? This list is the best!


More specifically it's a "precious metals" system, not just gold.


> Gold uses Troy weights unless otherwise specified, while feathers use the normal system.

“avoirdupois” (437.5 grain). Both it and troy (480 grain) ounces are “normal” for different uses.


The feathers are on the moon


Carried there by two birds that were killed by one stone (in a bush)


Ounces can measure both volume and weight, depending on the context.

In this case, there's not enough context to tell, so the comment is total BS.

If they meant ounces (volume), then an ounce of gold would weigh more than an ounce of feathers, because gold is denser. If they meant ounces (weight), then an ounce of gold and an ounce of feathers weigh the same.


> Ounces can measure both volume and weight, depending on the context.

That's not really accurate and the rest of the comment shows it's meaningfully impacting your understanding of the problem. It's not that an ounce is one measure that covers volume and weight, it's that there are different measurements that have "ounce" in their name.

Avoirdupois ounce (oz) - A unit of mass in the Imperial and US customary systems, equal to 1/16 of a pound or approximately 28.3495 grams.

Troy ounce (oz t or ozt) - A unit of mass used for precious metals like gold and silver, equal to 1/12 of a troy pound or approximately 31.1035 grams.

Apothecaries' ounce (℥) - A unit of mass historically used in pharmacies, equal to 1/12 of an apothecaries' pound or approximately 31.1035 grams. It is the same as the troy ounce but used in a different context.

Fluid ounce (fl oz) - A unit of volume in the Imperial and US customary systems, used for measuring liquids. There are slight differences between the two systems:

a. Imperial fluid ounce - 1/20 of an Imperial pint or approximately 28.4131 milliliters.

b. US fluid ounce - 1/16 of a US pint or approximately 29.5735 milliliters.

An ounce of gold is heavier than an ounce of iridium, even though it's not as dense. This question isn't silly, this is actually a real problem. For example, you could be shipping some silver and think you can just sum the ounces and make sure you're under the weight limit. But the weight limit and silver are measured differently.


No, they're relying on the implied use of Troy ounces for precious metals.

Using fluid oz for gold without saying so would be bonkers. Using Troy oz for gold without saying so is standard practice.

Edit: Doing this with a liquid vs. a solid would be a fun trick though.




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