Post #461612

2026-02-28 21:06 UTC

Q1: Which is heavier: a kilogram of gold or a kilogram of feathers? Q2: Which is heavier: a pound of gold or a pound of feathers? Q3: Which is heavier: an ounce of gold or an ounce of feathers? (1/3, answers in next post)

Replies (7)

@TobyBartels@mathstodon.xyz 2026-02-28 21:06

A1: It's a trick question; they weigh the same amount. A2: It's a doubly trick question; the pound of feathers weighs more. A3: It's a triply trick question; the ounce of gold weighs more. (2/3, explanations in next post)

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@nyrath@spacey.space 2026-02-28 22:55

@TobyBartels I remember this from a book of brain teasers, which i read in the early 1960s. Gold is measured with troy pounds, while feathers are measured with avoirdupois pounds. The troy ounce is heavier than the avoirdupois ounce, and the troy pound is lighter than the avoirdupois pound.

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@Gaelan@cathode.church 2026-03-01 09:30

@TobyBartels hmmm, but can you buy more weight in gold or feathers for £1

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@ProphetsCross@mastodon.social 2026-03-01 12:34

@TobyBartels

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@tiredbun@akko.wtf 2026-03-01 12:49

@TobyBartels I heard that they weight the same amount in the atmosphere of the earth, but their objective weight is slightly different in vacuum, as air pressure changes weight ever so slightly (like water pressure allows objects with high volume to float), so feathers are a bit heavier if measured in earth.

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@n3wjack@mastodon.social 2026-03-02 07:33

@TobyBartels So it turns out the Imperial system is even worse than I thought.

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@TransGal4872@mk.absturztau.be 2026-03-01 12:18

@TobyBartels@mathstodon.xyz this has to do with troy pounds doesn't it?

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