A jet airplane in level flight has a mass of 8.63 104 kg, and the two wings have

Question

A jet airplane in level flight has a mass of 8.63 104 kg, and the two wings have an estimated total area of 91.0 m2. (a) What is the pressure difference between the lower and upper surfaces of the wings? Pa (b) If the speed of air under the wings is 233 m/s, what is the speed of the air over the wings? Assume air has a density of 1.29 kg/m3. Incorrect: Your answer is incorrect. . m/s (c) Explain why all aircraft have a "ceiling," a maximum operational altitude. The density of air ---Select--- decreases increases Correct: Your answer is correct. . with increasing height, resulting in a ---Select--- greater smaller Correct: Your answer is correct. . pressure difference. Beyond the maximum operational altitude, the pressure difference can no longer support the aircraft

Explanation / Answer

force F = (P2-P1)*A

In equilibrium F = W eight of the plane = mg

(P2-P1)*A = m*g

pressure difference P2 - P1 = mg/A = (8.63*10^4*9.8)/91 = 9293.85 Pa

-------------

from Bernoullis principle

P1 + (1/2)*rho*v1^2 = P2 + (1/2)*rho*v2^2

p2-P1 = (1/2)*rho*(v1^2 - v2^2)

P2 = pressure at the bottom

P1 = pressure on the top

v2 = speed of air at the bottom

v1 = speed of air on the top

9293.85 = (1/2)*1.29*(v1^2-233^2)

v1 = 262.1 m/s <<<-------answer

Related Questions

Navigate

• Browse (All)
• Browse A
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.