Consider a rectangular wing with a NACA 0009 airfoil section spanning the test section of a wind tunnel. The test section airflow conditions are sea level standard with a velocity of 176 ft/s. The wing is at an angle-of-attack of 4 degrees, and the wind tunnel force balance measures a lift of 29.5 lbf. You are solving for the area of the wing. Write the equation in terms of variables first and then solved for the area with values. (You do not need to define in words what each of the variables are. If needed, assume the smallest Re that you have data for.)

Amass of 1.5 kg of air at 120 kpa and 24°c is contained in a gas-tight, frictionless piston-cylinder device. the air is now compressed to a final pressure of 720 kpa. during the process, heat is transferred from the air such that the temperature inside the cylinder remains constant. calculate the boundary work input during this process.

The mass flow rate of the fluid remains constant in all steady flow process. a)- true b)- false

Aloaded platform of total mass 500 kg is supported by a dashpot and by a set of springs of effective stiffness 72 kn/m. it is observed that when the platform is depressed through a distance x = 12.5 cm below its equilibrium position and then released without any initial velocity; it reaches its equilibrium position in the shortest possible time without overshoot. find the position and velocity of the loaded platform 0.10 sec. after its release. if a further load of 400 kg is added to the platform, find, i) the frequency of damped vibrations, and i) the amplitude of vibration after 2 complete oscillations, given that the initial amplitude is 15 cm.