In scuba diving, a regulator is used so that the pressure of the air the diver breathes is close to that of the ambient water. A reckless swimmer decides to use a hose sticking out of the surface to breathe underwater while diving in a lake. When the air pressure in the lungs is at a pressure of around 0.120 atmospheres below the ambient pressure, lung injury may occur. Find the depth at which the swimmer would experience such a pressure differential.

Answer 1

weight of water/area= area*height*density*g/area

pressure=height*density*g=.120atm*101.3kpa

height=.120*101E3 /9.8E3 =about 1.24m

check: you know atmospheric pressure is about 10 meters, so .12 of that is 1.2m