• Frezik@lemmy.blahaj.zone
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    3 hours ago

    A similar size chunk of iron and coal would have done the experiment just fine. Any two objects of the same shape and size but significantly different densities.

    • missingno@fedia.io
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      3 hours ago

      If two objects have the same size and shape, the force applied by air resistance will be the same. However, if two objects have different mass, that same force will result in different acceleration.

      • psud@aussie.zone
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        40 minutes ago

        The acceleration will be 1G minus drag. The Earth is sufficiently larger than anything one would drop off a tower so the weight of the dropped thing doesn’t matter at all

        How does your model of the universe explain the hammer and feather dropped on the moon by Apollo 15’s David Scott landed at the same time?

        Ed. There is an effect of buoyancy that will make denser things fall faster. It becomes noticeable in distances where the dropped items reach terminal velocity or on more dense media where buoyancy is more significant.

        In air over short distances buoyancy is negligible, in vacuum there is none

        • missingno@fedia.io
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          51 minutes ago

          minus drag

          On Earth, this is the part that makes it so that objects do not fall at the same speed.

          on the moon

          This is the type of experiment they could not do 2000 years ago.

        • Rivalarrival@lemmy.today
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          40 minutes ago

          Read their claim again: they are specifically describing the effect of air resistance. Their claim is perfectly consistent with the lunar feather/hammer experiment.

        • mnemonicmonkeys@sh.itjust.works
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          1 hour ago

          The Earth is sufficiently larger than anything one would drop off a tower that the weight of the dropped thing doesn’t matter at all

          F=ma.

          Two items of the same shape will have the same amount of air resistance. If they have significantly different masses, the two object experience commensurately different accelerations (or reduction in acceleration), even if the force is the same.

          If you take a balloon full of tetrahexofluroride (a gas 6x the density of air) and a chunk of iron the exact same size and shape and throw them off a building, I guarantee the iron chunk will hit first.

          How does your model of the universe explain the hammer and feather dropped on the moon by Apollo 15’s David Scott landed at the same time?

          It’s called a vacuum, which is famous for not having air resistance. Y’know, the thing we’re talking about?

          To perform the experiment properly on Earth where there is air resistance, you need to pick a shape and range of masses that minimize the effect of air resistance

          • psud@aussie.zone
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            44 minutes ago

            You are wrong. Falling in a medium is slowed by buoyancy and drag

            F=ma has nothing to do with it

      • StellarExtract@lemmy.zip
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        2 hours ago

        While that is true, two properly selected objects (such as the ones mentioned above) can reduce the effect of air resistance to levels negligible to human perception, demonstrating that heavier objects do not intrinsically fall faster.

        • ColeSloth@discuss.tchncs.de
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          35 minutes ago

          Not at all. Our air is made up of physical objects (molecules of oxygen and nitrogen, mostly). Things with more mass, more quickly knock those out of the way.

          For a demonstration you can see and more easily wrap your head around, take something just barely heavier than water, and a similarly sized heavy rock and drop them in a pool. You’ll see how much quicker the rock gets to the bottom, because it displaces the water so much faster. Our atmosphere is the exact same.

        • psud@aussie.zone
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          1 hour ago

          The difference is the different buoyancy of the balls in air. That’s negligible.