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Problem with fluids

human lung can withstand an inside/outside difference of about .06 atm. if a diver is using a snorkel to breathe, how far below the water surface can he get before he is risking lung damage? pressure of outside is the water pressure at that depth, while pressure inside is the pressure of the air being breathed.

this is what i have......

.06 = 1.01e5 / (1.01e5 + 1000(9.8)(h)

the above calc comes from equation P= Po +density(g)(h).......1000 is the density of water given to us, and 1.01e5 is atmospheric pressure,,,,, by solving for h i get an answer of 161.45 m........and not suprisingly im way off, the correct answer is .62m where did i go wrong here
 

siddharth

Homework Helper
Gold Member
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See the units for pressure you used on LHS and RHS
 
im not sure i understand what you are saying
 

siddharth

Homework Helper
Gold Member
1,110
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On the left hand side you used pressure in atmospheres (0. 06atm). Whereas in the right hand side you used pressure in Pascals (1.01* 10^5 Pascals).
Since the SI unit of pressure is Pascals (and you used value of g as 9.8 m/sec^2, which is expressed in SI units), you should convert the pressure from atmospheres to Pascals before you calculate.
 
you are right on siddarth,.,,,, thanks a lot
 

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