Change in volume with respect to depth

[Iota]

I can work out these equations when the pressure and volumes are given, but I've forgotten how to do it with those that only state depth:

 

A scuba diver inhales air at a depth of 10m and ascends to 1m, holding their breath. If their normal lung volume is 0.500dm³, to what will this expand during the ascent?

 

I've been looking at it a while and can't work it out. The pressure decreases and volume increases as they ascend, but I don't know how to work out the factor by which the volume increases.

[doG]

Normal lung volume is a function where a variable representing pressure is at a value that coincides with zero depth. Pressure is a function dependent on depth. Try writing the equation for pressure as a function of depth and then try substituting that equation as the variable for pressure in the function for lung volume.

[alibaba441]

Pv = nRT (http://en.wikipedia.org/wiki/Ideal_gas)

 

P1V1 = P2V2

 

P1 = pressure at 9m

V1 = 0.5dm cubed

 

P2= pressure at 1m

V2 = your answer

 

what is P1 and P2?

 

P = Po + density*g*height ( hydrostatic pressure equation https://en.wikipedia.org/wiki/Fluid_statics)

 

where Po is the atmospheric pressure

 

 

P1 = Po + 1000kg/mcubed * 9.81 m/s^2 * 1m = 101,000 + 9810 = 110,000 Pa

P2 = Po + 1000kg/mcubed * 9.81 m/s^2 * 9m = 101,000 +88,290 = 189,000 Pa

 

ill let you do the rest

Edited May 24, 2013 by alibaba441