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[Dsarker]

Feathers are indivilly lighter, larger, and flatter. They generate more air resistance. This means that their acceleration due to gravity is lessened, and so they weigh less.

[Kogut]

Feathers are indivilly lighter, larger, and flatter. They generate more air resistance. This means that their acceleration due to gravity is lessened, and so they weigh less.

Sorry, this is a giant mistake - you think about terminal velocity.

[Dsarker]

No, I'm pretty sure I'm not. Terminal velocity would be lowered by having more air resistance, but that is because of the gravitic potential energy being frustrated.

[Neonivek]

Isn't terminal velocity Air Resistance - Gravity anyhow?

[Dsarker]

Terminal velocity is hit when air resistance equals gravity.

[Cruxador]

Feathers are indivilly lighter, larger, and flatter. They generate more air resistance. This means that their acceleration due to gravity is lessened, and so they weigh less.

No, I'm pretty sure I'm not. Terminal velocity would be lowered by having more air resistance, but that is because of the gravitic potential energy being frustrated.

That's not right. Weight of an object is the force that gravitation exerts upon a body, equal to the mass of the body times the local acceleration of gravity. Downwards acceleration is net weight. Part of that can be negated as an object exerts its downward force on air molecules and those molecules (pursuant to Newton's third law) exert force back and decrease the object's net force. Part of that can also be negated when an object rests on another solid, such as a scale, and its acceleration is brought to zero. But that doesn't mean an object is weightless while being weighed.

[Dsarker]

I never said an object would be weightless. I said it would weigh less.

[Cruxador]

I never said an object would be weightless. I said it would weigh less.

I know you didn't explicitly say that. I extended your definition to make it's incorrectness more obvious. An item laying at rest on a solid surface has no acceleration. By your definition, the object is thus weightless. This is the case even when the object is a scale, with the rather ludicrous implication that an item is weightless while being weighed.

Terminal velocity is hit when air resistance equals gravity.

Not quite. It's when air resistance equals weight. When that happens, the net force is equal to zero and there is no acceleration. Note that while freefall is sometimes referred to as being weightless (perhaps this is the source of your misapprehension?) this is not actually the case.

[Dsarker]

Well, you're wrong on both counts.

Firstly, acceleration is going on when something is on top of a solid surface. Acceleration due to gravity, however, is equalised by the resistance provided by the solid surface.

Secondly, you are weightless in freefall, as weight is provided by the resistance against gravity.

[dree12]

Weight is a FORCE, not an accelleration. A kilogram of feathers weighs less than gold because it has a higher buoyancy in the gaseous fluid around it, not necessarily from air resistance. For example, a kilogram of nitrogen weighs nearly nothing because it almost floats in our atmosphere. A kilogram of uranium, on the other hand, weighs nearly as much as [m * g]. Notice that buoyancy is not equivalant to air resistance, as it does not concern kinetic friction.

A good approximation for reasonably geometric objects could be:

weight (n) = mass (kg) * magnitude (m/s²) - air density (kg/m³) * volume (should actually be volume displaced, but the unit is still m³) * magnitude (m/s²)

Firstly, acceleration is going on when something is on top of a solid surface. Acceleration due to gravity, however, is equalised by the resistance provided by the solid surface.

Force is equalized, not accelleration. An object with equalized forces is not accellerating.

This is the case even when the object is a scale, with the rather ludicrous implication that an item is weightless while being weighed.

Weight is not an accelleration, it is a force. The force of gravity is not necessarily the weight for practical purposes, however. You could try arguing that a kilogram of helium weighs the same as a kilogram of uranium - even many scientists would disagree.

[Draegur]

I'm not all too impressed, to be honest. The only video they have is of the material being slooowly compressed to 50% size, and although it's pretty neat-o seeing it gradually snap back to shape, I don't see *any* videos of people handling it, tossing it around, stacking things on it.. For all we know, despite its 'to-scale' strength, maybe it'd come apart in our hands like actual IRL sugar-based candyfloss. If they really wanted to demonstrate its lightness, they'd prepare an extremely long plank of it and demonstrate a person lifting it entirely off of a table while maintaining it at a perfectly horizontal orientation using only their two pinkie fingers on the end. Seeing these static images don't give us any idea whatsoever of its actual handling and macro-scale structural integrity!

[Cruxador]

Firstly, acceleration is going on when something is on top of a solid surface. Acceleration due to gravity, however, is equalised by the resistance provided by the solid surface.

There is no acceleration going on, as acceleration is change in speed or direction of travel, and the item in the example was specified to be at rest. Unless you meant to imply that the object would be at rest regarding one point of reference (say, the earth) and accelerating compared to a different frame of reference (such as the sun or the center of the galaxy) in which case that's retarded and serves no purpose besides obfuscation of the point.

Secondly, you are weightless in freefall, as weight is provided by the resistance against gravity.

Even with this new definition (which is totally different from your previous definition) you're wrong. When at terminal velocity, air molecules are exerting resistance against gravitational force equivalent to what would normally be termed the object's weight. That's why there's no acceleration in the first place.

But I tire of this discussion and I suspect you're just trolling anyway, so here are some definitions:

For weight:
Google: A body's relative mass or the quantity of matter contained by it, giving rise to a downward force; the heaviness of a person or thing.
Dictionary.com: the force that gravitation exerts upon a body, equal to the mass of the body times the local acceleration of gravity: commonly taken, in a region of constant gravitational acceleration, as a measure of mass.
TheFreeDictionary.com: The force with which a body is attracted to Earth or another celestial body, equal to the product of the object's mass and the acceleration of gravity.
Wikipedia: In science and engineering, the weight of an object is the force on the object due to gravity.
Merriam-Webster: the force with which a body is attracted toward the earth or a celestial body by gravitation and which is equal to the product of the mass and the local gravitational acceleration

Those make reference to gravitational acceleration, which it now occurs to me you may have been confusing with acceleration due to gravity. Honestly, that would be a fairly understandable mistake. However they are not the same; gravitational acceleration is a pure measure of the force of gravity; it assumes a vacuum. Earth's gravitational acceleration is about 9.8 meters per second per second.

[Loud Whispers]

Feathers are indivilly lighter, larger, and flatter. They generate more air resistance. This means that their acceleration due to gravity is lessened, and so they weigh less.

We can assume both are weighed in a vacuum. And are stationary. Gravity remains constant, the force it displays never "lessens", as shown by your weight not randomly changing. Oh and weight is the measurement of force exerted by gravity.

Oh and mass is measured in grams. Guess what I was talking about. Yup, the mass.

NERDPWNAGE

I'm not all too impressed, to be honest. The only video they have is of the material being slooowly compressed to 50% size, and although it's pretty neat-o seeing it gradually snap back to shape, I don't see *any* videos of people handling it, tossing it around, stacking things on it.. For all we know, despite its 'to-scale' strength, maybe it'd come apart in our hands like actual IRL sugar-based candyfloss. If they really wanted to demonstrate its lightness, they'd prepare an extremely long plank of it and demonstrate a person lifting it entirely off of a table while maintaining it at a perfectly horizontal orientation using only their two pinkie fingers on the end. Seeing these static images don't give us any idea whatsoever of its actual handling and macro-scale structural integrity!

I don't suppose it's easy for them to produce large amounts of this wonder-candy just yet, but I agree.

WHERE IS MY NICKEL-PHOSPHOROUS JUMPER?
[Or socks for that matter]
[Or hammer striking a wafer stack of this]
[Or someone karate chopping it in vain]

[GreatWyrmGold]

1 kilograms of rocks = 1 kilograms of feathers

Same mass, not same weight.

Only if you want to get technical. Yes, if the kilo of rocks is in an area of different gravitational acceleration, their weights will be different. Let's assume for the sake of the argument that they aren't. Same weight.

[Armok]

If something's hitting your spaceship, you're probably already screwed. A peanut in Earth's orbit can hit a space station with the equivalent force of a 50. Bullet 

Interestingly, because throughout the history of manned space exploration waste management (human waste that is) has largely consisted of dumping it overboard (or however we are supposed to refer to it on a spaceship), the most common thing you're likely to be hit by in low Earth orbit is shit travel in excess of 30,000 miles an hour. Frozen solid into something much like extremely unhygienic steel. This actually causes damage in the millions each year to satellites.

Somhow this didn't get throguh the forst time I tried to post it, apperently:

When it eventually does impact something, it's guaranteed to be some kind of air conditioning unit. Or maybe just a devote follower of something.