Pressure & Air Volume
Salt Water
0 ft
33 ft
66 ft
99 ft
Calculating Air Volume Changes
You can calculate exact changes in air volume by using a simple calculation. It is:
In the example to the left, a balloon contains 8 cubic inches of air at 33 feet. It is then pulled down to 99 feet, and we want to know the new volume.
First, we need to determine the original and final pressures. Since this is salt water, the pressure at 33 feet is 2 ata, and at 99 feet the pressure is 4 ata. Next, we determine the original volume, which is 8 cubic inches. So our formula will look like this:
The ratio equals 1/2, and 1/2 of 8 equals 4. So the balloon's new volume at 99 feet would be 4 cubic inches.
In the example to the left, a balloon contains 8 cubic inches of air at 33 feet. It is then pulled down to 99 feet, and we want to know the new volume.
First, we need to determine the original and final pressures. Since this is salt water, the pressure at 33 feet is 2 ata, and at 99 feet the pressure is 4 ata. Next, we determine the original volume, which is 8 cubic inches. So our formula will look like this:
The ratio equals 1/2, and 1/2 of 8 equals 4. So the balloon's new volume at 99 feet would be 4 cubic inches.
