How to Calculate the Pull of Air Underwater
- 1). Multiply the water's depth, in meters, by its density, which is approximately 1,025 kg per cubic meter in the ocean. For example, if the air bubble is 2,000 feet below water, multiply 2,000 by 1,025, giving 2,050,000.
- 2). Multiply the result by acceleration due to gravity, which is 9.81 newtons per kilogram. So, 2,050,000 multiplied by 9.81 is 20,110,500. This is the water's pressure, measured in pascals.
- 3). Divide this pressure by atmospheric pressure, which is 101,325 pascals. So, 20,110,500 divided by 101,325 is 198.48. This is the water's pressure, measured in atmospheres.
- 4). Divide the air's volume at the surface by this pressure. For example, if the air has a volume of 0.1 cubic meters at the surface, divide 0.1 by 198.48, giving a volume of approximately 0.0005 cubic meters.
- 5). Multiply this volume by water's density. So, 0.0005 times 1,025 gives a mass of 0.5125 kg.
- 6). Multiply this mass by specific gravity, which is 9.81 newtons per kilogram. So, 0.5125 times 9.81 gives a force of 5.027 newtons pulling the air upward.
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