The human lungs can function satisfactorily up to a limit where the pressure difference between the outside and inside of the lungs is 1/20 of an atmosphere. If a diver uses a snorkel for breathing, how far below the water can she swim? Assume the diver is in salt water whose density is 1025 kg/m3.

Answer 1

the weight of a 1 meter tube of water h meters high...

weight=9.8*1025*h*1m^2 N
pressure= 9.8*1025*h Pa
lung pressure=1/20*101.3 kPa

set them equal
.05*101.3e^3 Pa=9.8*1025*h

h= .... about a half meter.