# Fluids and Pressure

Ok, I got this scuba diver and he has a tank that is 0.015 meters cubed and filled with compressed air at an absolute pressure of 2.02e7 Pa. Assuming air is consumed at a rate of 0.03 meters cubed per minute and the temperature is constant, how long can this diver stay under water at a depth of 30.0 meters? Assuming the density of the water is 1025 kilograms per meter cubed

I found the pressure at 30 ft. below, but I didn't really know what to do with it. Help??

Last edited:

## Answers and Replies

Andrew Mason
Science Advisor
Homework Helper
myogi said:
Ok, I got this scuba diver and he has a tank that is 0.015 meters cubed and filled with compressed air at an absolute pressure of 2.02e7 Pa. Assuming air is consumed at a rate of 0.03 meters cubed per minute and the temperature is constant, how long can this diver stay under water at a depth of 30.0 meters? Assuming the density of the water is 1025 kilograms per meter cubed.
I found the pressure at 30 ft. below, but I didn't really know what to do with it.
You will need to find the pressure at a depth of 30 metres.

I assume that the .03 m^3/min. is the volume rate of air at a depth of 30 m. So work out how much volume the tank contains when let out with the ambient pressure at 30 m. ($V \propto 1/P$). With that total volume, work out the consumption time from the consumption rate.

Keep in mind, if he stays that that long at 30 m. he will die. He needs some air to get down to 30m and some air to get back. He has to come up gradually.

AM