Counter-Intuitive Science

I think yes, albeit only slightly. For a latex party balloon the interior pressure would be more different.Note, however, that lyx2no is talking about a hot air balloon, one that is not closed off at the bottom.Moose

Is the issue pressure or density? Why would the pressure be higher at one point then another?

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Anyone so limited that they can only spell a word one way is severely handicapped!

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Now that I didn't know. Can I see the math/reasoning?

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You can see the math in this paper: Maruyama T and Kimura M (1974), "A note on the speed of gene frequency changes in reverse directions in a finite population." Evolution 28: 161—163 (although a special case had been worked out earlier). The basic intuition (to the extent that there is one) is that the only way a deleterious allele is going to fix is if it experiences a number of substantial "lucky" upward fluctuations; if that's going to happen, it's probably going to happen quickly, since otherwise selection will drive it to or near extinction. Of course, the probability that the deleterious allele will fix is much lower than for the beneficial allele, but the time to fixation conditional on fixation turns out to be the same, for a given selection coefficient.

Yes, though perhaps only very slightly greater. That difference is what holds the film (surface of the bubble) taut.

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Jesus was a liberal hippie

Okay, then next step.If the pressure was greater at one point than at another what shape should be seen?

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Anyone so limited that they can only spell a word one way is severely handicapped!

Oh, here's one that happened to me.Once I was walking towards a set of sliding doors. I noticed them open and close for a group of people walking ahead of me, but when I came to them they wouldn't open. Judging that the sensors weren't sensitive enough to detect my modest weight, I decided to leap vertically in the air in the hope that when I came down the extra force of my impact would open the doors. It did not, and couldn't have done.Why not?

Innies and outies?

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Anyone so limited that they can only spell a word one way is severely handicapped!

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Once I was walking towards a set of sliding doors. I noticed them open and close for a group of people walking ahead of me, but when I came to them they wouldn't open. Judging that the sensors weren't sensitive enough to detect my modest weight, I decided to leap vertically in the air in the hope that when I came down the extra force of my impact would open the doors. It did not, and couldn't have done.

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Why not?

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Even though you didn't realize it, you were already dead, and ghosts have no weight?

Throw a rope over a pulley. Give one end to a 160-pound US Marine and the other end to his 180-pound sickly grandpa. Who lifts whom?

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"I'm Rory Bellows, I tell you! And I got a lot of corroborating evidence... over here... by the throttle!"

The following assumes the burner is not operating, and it hasn't been recently operating. Temperature, pressure, and density gradients are at equilibrium.My image is that the interior and exterior temperature, pressure, and density are the same at the bottom. There is no physical barrier to separate interior from exterior, and they are at equilibrium.At the balloon top, the air is at its highest temperature, highest pressure, and lowest density. The higher T dominates over the higher P, and thus the lower density.The pressure/height in the balloon analogy would be an inverted pressure/depth in water situation. Greater height results in greater pressure like greater depth results in greater pressure.No, I don't have the physics to back this up, and I'm not going to pursue such. I have nothing further to say beyond "I may be wrong" - Let a real physicist take it from here.MooseAdded by edit (Gas laws):
Boyle's law - Wikipedia
Charles's law - WikipediaEdited by Minnemooseus, : See above.

The shape does not depend on absolute pressure, but on the difference of pressure between inside air and outside air. For an approximately spherical bubble, that difference needs to be constant. The absolute pressure is lower at the top of the bubble than at the bottom, though the difference is probably too small to measure.

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Jesus was a liberal hippie

My favourite example of counterintuitive is what you get when you cut a Mobius strip in half down it’s length. And then what you get if you cut the result down it’s length one third in from the edge.Other good ones would be that you can cover a plant with ice to protect it from freezing, married men live longer than bachelors and the behaviour of anything bigger than a galaxy.

I refer you to Wikipedia's list of common misconceptions. In fact, we're closest to the sun in the northern hemisphere's winter. I'd also point out that since winter/summer don't co-incide in the hemispheres it should be obvious that the Earth's orbit can't be the primary driving factor.Edited by Mr Jack, : Addendum and clarification.

About a decade ago, I tried to see what difference that 3 million miles would make. In our world atlas, I compared the winter and summer time average temperatures of regions the same mid-latitude north and south six months apart: ie, I compared our winter in Jan to their winter in July and our summer in July to their summer in Jan. And I chose what appeared to be roughly equivalent land masses, Australia and the US mid-west.What I found was that the Australian summer, which is at perihelion (04 Jan, closest to the sun) was on average about 1.9C (3.4F) warmer than the US summer, which is at aphelion (04 Jul, farthest from the sun). So the temperature difference that 3 million miles make is a few degrees.Of course, there are other meteorological factors that come into play which undoubtedly influence those results, so my findings are by no means conclusive. But I think that it does still give us some perspective.

If the pulley and the rope are almost straight up from the 2 the marine would lift himself trying to lift the grandpa. If the rope is longer so the marine can put the rope at an angle by walking a few feet away from the grandpa he can lift the grandpa if he is strong enough