Help with pressure-force problem

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SUMMARY

The discussion focuses on calculating the force exerted on a car door submerged in water at a depth of 13.7 meters. The user applied the formula for force, F = pressure * area, incorporating atmospheric pressure and hydrostatic pressure. The calculated force was 351582 N, but the user suspected an error in their approach. Key considerations include the role of atmospheric pressure and the potential impact of air inside the car on the overall pressure calculation.

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  • Understanding of hydrostatic pressure principles
  • Familiarity with the formula for calculating force (F = pressure * area)
  • Knowledge of atmospheric pressure (101325 N/m²)
  • Basic concepts of fluid mechanics
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  • Review hydrostatic pressure calculations in fluid mechanics
  • Learn about the effects of buoyancy on submerged objects
  • Explore the implications of air pressure in closed systems
  • Study the principles of pressure distribution on submerged surfaces
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Students studying physics, particularly those focused on fluid mechanics, as well as educators looking for practical examples of pressure calculations in real-world scenarios.

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Homework Statement



A car misses a turn, sinks into a shallow lake, coming to rest on its side with the door horizontal and at a depth of 13.7 m. If the area of the car door is 0.67 m^{2}, what is the force exerted on the outside of the door by the water?

Homework Equations



Force = pressure * area

The Attempt at a Solution



p_total = p_atm + \rho * g * h

F = (p_atm + \rho * g * h)/area

F = (101325 N/m^{2} + (1000 kg/m^{3} * 9.8 m/s^{2} * 13.7 m)) / .67 m^{2} = 351582 N

That's what I've done so far, but it isn't the right answer, can someone help point me in the right direction? I know I did something wrong or forgot something but don't know what it is. Thanks in advance!
 
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Maybe the car is still filled with air so that the atmospheric pressure cancels out (it takes some time to fill with water anyway even if the windows are open).
 
No, it tells me to not forget to add the atmospheric pressure.
 

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