# Pressure on wing of plane

1. Dec 3, 2008

### Husker70

1. The problem statement, all variables and given/known data
An airplane has a mass of 1.60 x 10^4kg and each wing has an area of 40.0m^2.
During level flight, the pressure on the lower wing surface is 7.00x10^4Pa. Determine
the pressure on the upper wing surface?

2. Relevant equations
Newtons third law

3. The attempt at a solution
As I read through about airplane and wing I see that the force on the wing
has an equal and opposite reaction force. Also the curvature of the wing is a factor.
This problem states no curvature? The wings are assumed parellel to plane.
Is this simply 7.00x10^4 for the top? from the information given or am I missing
something
Thanks,
Kevin

2. Dec 3, 2008

### mgb_phys

You are reading too much into the question.
All it is asking is how much force is needed to lift the plane's mass.
Given the wing area how much pressure difference is needed to supply this force.

3. Dec 3, 2008

### Husker70

Thanks,
hmmm. Don't know what to do with the mass
F = PA so that is to be (7.00x10^4)(40.0m^2) x 2 = 5.6x10^6N
I might need a clue from there.
Thanks,
Kevin

4. Dec 3, 2008

### mgb_phys

Force down = weight = mg
Force up = pressure difference * area

It want's the total pressure so you need to subtract the pressure difference from the absolute pressure on the bottom