Dimensional Analysis on Lift Equation not working out?
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Dimensional Analysis on Lift Equation not working out?
Hello,
I am showing that the equation for lift on a wing is
L=1/2 Cl (air density) (Area of Wing) Velocity^2
However, the dimensions aren't working out.
L is kg ; Cl is dimensionless; Air density is kg/m^3; Area is m^2; Velocity is m/s
If you work the dimensions it does not work out. You get L in kg and kg m on the other side.
What am I missing?
Thanks.
I am showing that the equation for lift on a wing is
L=1/2 Cl (air density) (Area of Wing) Velocity^2
However, the dimensions aren't working out.
L is kg ; Cl is dimensionless; Air density is kg/m^3; Area is m^2; Velocity is m/s
If you work the dimensions it does not work out. You get L in kg and kg m on the other side.
What am I missing?
Thanks.
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Hello,
I am showing that the equation for lift on a wing is
L=1/2 Cl (air density) (Area of Wing) Velocity^2
However, the dimensions aren't working out.
L is kg ; Cl is dimensionless; Air density is kg/m^3; Area is m^2; Velocity is m/s
If you work the dimensions it does not work out. You get L in kg and kg m on the other side.
What am I missing?
Thanks.
I am showing that the equation for lift on a wing is
L=1/2 Cl (air density) (Area of Wing) Velocity^2
However, the dimensions aren't working out.
L is kg ; Cl is dimensionless; Air density is kg/m^3; Area is m^2; Velocity is m/s
If you work the dimensions it does not work out. You get L in kg and kg m on the other side.
What am I missing?
Thanks.
Second, you are missing that lift is a force so it is in Newtons which is also (e.g. from F=ma) = kg*m/s^2
Sorry you didn't discover new physics, maybe next time
I get the joke, like "new math".
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To add to the tongue-in-cheek ‘new physics’, I’m glad Newton got there first. Imagine force’s being measured in Aviationluvers or Infrequentflyer789s
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Not sure if he was a grocer but I always think of apple's when I think of Newton.
Back to topic, the OP isn't the first person to have a "brain fart" and mix up mass and force in an equation.
Back to topic, the OP isn't the first person to have a "brain fart" and mix up mass and force in an equation.
I was confused when I was first saw that the dimensions of a force are M.L.T^-2
However, it’s obvious when you look at F = m.a
However, it’s obvious when you look at F = m.a