What’s heavier, a kilogram of steel or a kilogram of feathers?

There’s a test for this. You take the steel and the feathers up to the top of a tall tower, preferably one that leans over a bit so your steel and feathers fall without hitting the tower.

Then you drop them at exacly the same time.

Onto a person.

Then run down the steps and ask them which it is.


Makes more sense. He’s sizing them up - probing the depths of their ignorance. Trolling, essentially.

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This question has always irritated me. Excellent point: the question specifies mass (kg), and then asks about weight (measured in Newtons). However, the difference in weight is more significant than that that introduced by the difference in center of mass. Steel is denser than keratin (which is what feathers are made out of); so a kilogram of steel displaces less air than a kilogram of feathers. As a result, the kilogram of feathers is ever so slightly more buoyant in air than the kilogram of steel, and therefore exerts less downward force (in Newtons), which means that it weighs less.

Still, it’s around 450C at Venus’s surface and pressure is 90atm. I’m thinking even without oxygen to burn them, the feathers aren’t going to stay recognizably feathers for long.

Fun fact, the pressure is so high at Venus’s surface that the CO2 atmosphere isn’t actually a gas. It’s technically a supercritical fluid at that point.

I also just looked up the physical properties of keratin, and while I didn’t find a lot of cites, they all put its melting point somewhere between 140C and 200C, which means Venus’s surface temperature would definitely be destructive without needing combustion.


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