AliceInMyDreams

AliceInMyDreams t1_j5rb9cq wrote

Reply to comment by Ragidandy in If I had two cups of water, one normal size and one as big as a swimming pool and stirred them both with proportionally sized spoons, would the larger pool of water keep spiraling longer than the smaller? by r3volc

Everyone is saying that, but assuming the pool is an isotropocally scaled version of the cup, its energy scales with r^3, but the dissipation scales with S*v ~ r^2 * rw ~ r^3

Unless I'm too tired and missing something obvious this doesn't seem that simple

Edit : thinking about it for another minute I do believe I'm too tired after all, because I didn't take into account that the energy doesn't linearly scales with the volume, but rather in r^5 assuming constant angular velocity

And so r^5 >>> r^3 and the pool indeed triumphs over the cup

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