In a test experiment on a model aeroplane in a wind tunnel, the flow speeds on the upper and lower surface of the wing are `70 ms^(-1) and 63 ms^(-1)` respectivley. What is the lift on the wing if its area is `2.5 m^(2)`? Take the density of air is `1.3 kg m^(-3)`.

Explanation

From bernoullis equation `P_(2)-P_(1)=1/2 rho(v_(1)^(2)-v_(2)^(2))`
Upward force on the wing `F=(P_(2)-P_(1))A`, where A is area of the wing.
`F=1/2rho(v_(1)^(2)-v_(2)^(2))A=1/2xx1.3`
`(70^(2)-63^(2))xx2.5=1.5xx10^(3)N`