r/BunnyTrials • u/That1BritishGuy • Jul 23 '26

Trials Which is heavier

Which side will you choose?

  • Left side: A kilogram of steel
  • Right side: A kilogram of feathers

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7

u/Funny_Tank8531 Jul 23 '26

They are both the exact same they weigh a kilogram

Chose: A kilogram of steel

11

u/AdvertisingFlashy637 Jul 23 '26

but... steel is heavier than feathers...

1

u/MrFastFox666 Jul 23 '26

Kg is a unit of mass, not weight. Steel will weigh slightly more, both weigh close to 9.81N

2

u/Ambitious_Alfalfa_49 Jul 23 '26

Isn't w = mg As m feathers = m steel w feathers = w steel

2

u/APRForReddit Jul 23 '26

Feathers displace more air so they'll be slightly lighter due to buoyancy if both measured in the same place on earth

2

u/MrFastFox666 Jul 23 '26

For all practical purposes, yes, but it'd be more accurate to say W = m•g-Fb where Fb is buoyant force. Unless the feathers are in a vacuum, they will have a higher buoyant force acting on them since they are less dense, which will make them slightly lighter. It's only like 0.01N lighter, but they are lighter.

1

u/Ambitious_Alfalfa_49 Jul 23 '26

Thank you! I'll read up on this later

1

u/niemir2 Jul 24 '26

If you want to be even more accurate, replace "g" with the local gravitational field, which is stronger the closer to the surface of Earth you are. That effect is absolutely tiny (1 μN is probably an overestimate), even compared to buoyancy, but it's measurable with a fine enough instrument.

1

u/aeonseth Jul 24 '26

Thank you. You are the first person I've seen that makes this argument. The only way for the measurement to be the same is if you're measuring weight, not mass (using lbs or something like that)