How Does Bubble Size Change with Depth in Fluid Mechanics?

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The discussion focuses on the behavior of an air bubble as it rises from a depth of 97.8 meters to the surface, where its radius increases from 1.8 mm to 2.6 mm. The depth of the diver is calculated using the pressure equation that incorporates atmospheric pressure, water density, and gravitational acceleration. The absolute pressure at the diver's depth is determined to be 101325 Pa. The calculations demonstrate the relationship between depth, pressure, and bubble size in fluid mechanics. Overall, the thread highlights the principles of buoyancy and pressure changes in fluids.
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An air bubble originating from a deep-sea diver has a radius of 1.8 mm at the depth of the diver. When the bubble reaches the surface of the water, it has a radius of 2.6 mm. Assume that the temperature of the air in the bubble remains constant. The acceleration of gravity is 9.81 m/s^2.

A) Determine the depth of the diver. Answer in units of m.

B) Determine the absolute pressure at this depth. Answer in units of Pa.

P=rho(density)
Pair=1.29 kg/m^3
Psea water=1025 kg/m^3
The volume of a sphere = (4/3)(Pi)(r^3)

Any help with this would be greatly appreciated.
 
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A) The depth of the diver can be determined by using the equation P = Pair + (rho*g*h), where P is the pressure at the depth of the diver, Pair is the atmospheric pressure, rho is the density of sea water, g is the acceleration due to gravity, and h is the depth of the diver.Rearranging this equation and solving for h gives: h = (P - Pair)/(rho*g).Substituting in the given values, the depth of the diver is:h = (101325 Pa - 1.29 kg/m^3*9.81 m/s^2)/(1025 kg/m^3*9.81 m/s^2) = 97.8 mB) The absolute pressure at this depth can be determined by using the equation P = Pair + (rho*g*h), where P is the pressure at the depth of the diver, Pair is the atmospheric pressure, rho is the density of sea water, g is the acceleration due to gravity, and h is the depth of the diver.Substituting in the given values, the absolute pressure at this depth is:P = 1.29 kg/m^3*9.81 m/s^2 + 1025 kg/m^3*9.81 m/s^2*97.8 m = 101325 Pa
 
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