Calculating Pressure Outside a Box: Bernoulli's Equation

AI Thread Summary
To calculate the pressure outside a box using Bernoulli's equation, the atmospheric pressure is given as 101325 Pa, with air moving at 45 m/s and a density of 1.3 kg/m^3. The equation used is P + 1/2(roe)(v)^2 = Patm, leading to the calculation P + 1316.25 Pa = 101325 Pa. This results in an external pressure of 100008.75 Pa, assuming the box is open with static air inside and airflow over the opening. The discussion emphasizes the importance of fully defining the problem, as Bernoulli's equation represents energy conservation. The calculations provided are confirmed to be correct.
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Homework Statement


Calculate pressure outside the box- ATM pressure is 101325 Pa, air moving outside the box is 45 m/s, air density is 1.3 kg/m^3

Homework Equations


P + 1/2(roe)(v)^2 = Patm

The Attempt at a Solution


P + 1/2 (1.3kg/m^3)(45m/s)^2 = 101325 Pa
P + 1316.25 Pa = 101325 Pa
P= 100008.75 Pa
 
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I guess the problem is an open box with static air inside and air blowing over the open end, in which case your computation is right.
But you need to define problems more fully.
 
Bernoulli's equation is an express of energy conservation. All terms have energy density dimensions and your calculation is correct.
 
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