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Pa Soda Bottle
A glass bottle of soda is sealed with a screw cap. The absolute pressure of the carbon dioxide inside the bott?
A glass bottle of soda is sealed with a screw cap. The absolute pressure of the carbon dioxide inside the bottle is 2.00 x 105 Pa. Assuming that the top and bottom surfaces of the cap each have an area of 4.30 x 10-4 m2, obtain the magnitude of the force that the screw thread exerts on the cap in order to keep it on the bottle. The air pressure outside the bottle is one atmosphere.
This is a gas hydraulic system the force on the cap is merely
[2X10^5(Pa) - 1(atm)] X 4.3*10^-4(m^2)
1Pa = 1 N/m^2......2X10^5(Pa) = 200X10^3(N/m^2)
1psi = 6895 N/m^2........14.7(psi)= 101.4X10^3(N/m^2)
differential pressure on the cap is 99X10^3(N/m^2)
force is 99X10^3(N/m^2)* 4.3X10^-4(m^2) = 42.57(N)