I'm not sure if this is the right place to put this; if it isn't, could someone point me in the right direction... thanks.(adsbygoogle = window.adsbygoogle || []).push({});

Anyhow, today in Physics (I am currently studying A-levels in England) we came across Stoke's Law. We were taught that, essentially it meant that the greater a spheres radius, the faster it falls through a fluid, and that weight does not factor in. However, I do not understand this; we have been taught that a larger object results in greater resistance from whatever it is moving in.

And I also wondered how it was possible to rule out weight as a factor. Surely, it is impossible to test the correlation between weight and the speed (keeping volume / radius the same) without changing density, which is something not being changed in the original experiment, therefore you can't really rule out weight (or can you...?).

These were my issues. I quickly wore out my teacher with my questions... perhaps I am missing some obvious point.

Anyhow, is there anyone here who could explain, in layman's terms (if that's not asking for too much), why a larger radius makes it descend faster (assuming weight does not matter), and how Stoke managed to rule out weight as the independent variable.

Have I missed something?

Thanks in advance

Riga-b

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# Confusion over Stoke's Law

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