Air is streaming past a horizontal air plane wing such that its speed in $ 120 m/s$ over the upper surface and $ 90 m/s$ at the lower surface. If the density of air is $1.3 kg$ per $metre^3 $ and the wing is $10 m $ long and has an average width of $2 m$, then the difference of the pressure on the two sides of the wing of ....... $Pascal$
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(a)From the Bernoulli's theorem
${P_1} - {P_2} = \frac{1}{2}\rho (v_2^2 - v_1^2)$$ = \frac{1}{2} \times 1.3 \times [{(120)^2} - {(90)^2}]$
$ = 4095\,N/{m^2}$or Pascal
${P_1} - {P_2} = \frac{1}{2}\rho (v_2^2 - v_1^2)$$ = \frac{1}{2} \times 1.3 \times [{(120)^2} - {(90)^2}]$
$ = 4095\,N/{m^2}$or Pascal
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