For an airplane in flight, the average speed of the air relative to the plane is

Question

For an airplane in flight, the average speed of the air relative to the plane is 316 m/s below the wings and 347 m/s above the wings (see the figure below). The bottom of each wing has a surface area of 30.1 m2. Calculate the lift, which is the net upward force of air on the plane.

PLEASE ROUND TO TWO DECIMAL PLACES! ALSO PLEASSEEE KEEP CHECKING THE COMMENTS. I HAVE POSTED THIS SAME PROBLEM 4 TIMES AND EVERYONE HAS GIVEN ME THE WRONG ANSWER AND THEY WONT MESSAGE BACK ON MY COMMENT, WHICH IS MAKING ME USE UP MY QUESTIONS LEFT FOR THIS SUBSCRIPTION PERIOD. THANK YOU

Explanation / Answer

From the question we have:

the average speed of the air relative to the plane is 316 m/s  below the wings

the average speed of the air relative to the plane is 347 m/s above the wings

The bottom of each wing has a surface area of 30.1 m2

To find: the lift, which is the net upward force of air on the plane.

Total wing area = (30.1 x 2) = 60.2m^2.
Pressure on bottom = 101,325Pa. (Assuming sea level atmospheric pressure)
Pressure on top = (101,325 x 316)/347 = 92,272.91 Pa.
Difference = (101,325 - 92,272.91) = 9,052.09Pa.
Lift = (9,052.09 x 60.2) = 544935.818N

Related Questions

Navigate

• Browse (All)
• Browse F
• Subjects

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