Final answer:
Air must move over the upper surface of a wing fast enough to create a pressure difference and generate lift, depending on air density and velocity. Air density at sea level is 1.29 kg/m³, and takeoff speed relative to the wing's underside is 60.0 m/s. The period of a fly's wing flap is the reciprocal of the flapping frequency, which is 1/200 seconds per flap for 200 Hz.
Step-by-step explanation:
Air Speed Calculation for Aircraft Lift.
To determine how fast air must move over the upper surface of an aircraft's wing to create the necessary lift force at takeoff, the principle of lift generation and Bernoulli's equation are used. Assuming that the wing must generate 1000 N of lift per square meter, we have to consider factors like air density and velocity. The air density at sea level is given as 1.29 kg/m³, and the airspeed relative to the bottom of the wing during takeoff is 60.0 m/s. Using Bernoulli's principle and the airspeed beneath the wing, we can find the required airspeed over the upper surface to produce the required lift. This depends on the changes in the pressure difference over the wings.
As for the fly's wing flap, the period of a wing flap can be found using the formula T = 1/f, where T is the period and f is the frequency. If a fly flaps its wings 200 times each second, the frequency f is 200 Hz. Therefore, the period T is the reciprocal of the frequency, which in this case would be 1/200 seconds per flap.