## Question

In a test experiment on a model aeroplane in a wind tunnel, the flow speeds on the lower and upper surfaces of the wing are *v* and respectively. If the density of air is and the surface area of the wing is *A*, the dynamic lift on the wing is given by

### Solution

Let *p*_{1} and *p*_{2} be the air pressures on the upper and lower surfaces of the wing. Then from Bernoulli’s theorem we have

where . Therefore, the pressure difference is

Force of dynamic lift = pressure difference surface area of wing

.

#### SIMILAR QUESTIONS

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