If an object is in the steady air (not wind) is it subject to an aerodynamic force? And if an object moves in the air, is there any aerodynamic force on it? What is the most important parameter in aerodynamic force?

The thermal expansion or contraction of a given metal is a function of the f a)-density b)-initial temperature c)- temperature difference d)- linear coefficient of thermal expansion e)- final temperature f)- original length

True or false (explain) (110)[111] is a slip system in bcc metals . the {111} family in fcc contains 8 planes. resolved shear stress (rss) in single crystals is just related to the applied stress. critical resolved shear stress (crss) in single crystal metals is direct proportional to the number of defects in the structure

Steam enters a converging nozzle at 3.0 mpa and 500°c with a at 1.8 mpa. for a nozzle exit area of 32 cm2, determine the exit velocity, mass flow rate, and exit mach number if the nozzle: negligible velocity, and it exits (a) is isentropic (b) has an efficiency of 94 percent