The atmosphere applies a large amount of pressure on us and if there is about 10 tons worth of atmospheric pressure on top of us, how can we get up from laying down?
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$\begingroup$ Put a flat piece of paper on a table, say a newspaper sized sheet. Can you lift it back up? I bet you can. physics.stackexchange.com/q/196324 $\endgroup$– user81619Sep 13, 2015 at 23:22
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$\begingroup$ Its because our bodies have the strength to withstand the pressure from the atmosphere. $\endgroup$– EthanSep 14, 2015 at 0:58
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1$\begingroup$ "Tons" is not a unit of pressure... $\endgroup$– DJohnMSep 14, 2015 at 3:14
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One answer is that atmospheric pressure doesn't weigh down on us, it presses in from all sides, including up from under us (since there are air gaps under your shoes and feet). So standing under the atmosphere isn't at all like standing under a 10-ton weight.
The long answer, which addresses tree new issue of "why doesn't atmospheric pressure crush us like empty soda cans," is that only pressure differences matter. The stuff inside you presses out with the same pressure as the air presses in, so you don't implode - or for that matter, explode.
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$\begingroup$ I suppose the difficult part to follow is why would a tiny gap under our feet "balance" the pressure on top, intuitively it does not add up, although obviously intuition is incorrect here. Although I do find it difficult to get out of bed, but that's just laziness more than air pressure:) $\endgroup$– user81619Sep 13, 2015 at 23:42
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$\begingroup$ @AcidJazz if you assume that the area of the top of your head and shoulders equals the area of the bottom of your feet (which I think is reasonably close) and assume that air pressure at your feet is equal to air pressure at your head (also reasonable) then the air lifts you up as much as it pushes you down, correct? $\endgroup$– AsherSep 14, 2015 at 4:30
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$\begingroup$ Sorry, I only saw your comment now, yes, my apologies for the delay in replying. I was trying to see things from the POV of the OP, not myself and my wording was badly put, apologies. The user formerly known as Acid Jazz. $\endgroup$– user81619Sep 15, 2015 at 22:17