Which one of the following scenarios accurately describes a condition in which resonance can occur? a. a column of air has a height equal to 1⁄8 of the wavelength of the sound waves produced by a tuning fork vibrating over the column of air in an open pipe that's partially immersed in water. b. a pipe's length is equal to 1⁄2 of the wavelength of the sound waves produced by a tuning fork vibrating over one end of the pipe that's open to the air at both ends. c. a person is holding a tuning fork on one end of a football field and another person is holding a separate tuning fork on the opposite end of the field. d. a vibrating tuning fork is struck and begins to vibrate as the object used to strike it is placed away from the tuning fork.

Which of the following represents an upright image? a. -do b. +m c. -m d. +do

Two horizontal plates with infinite length and width are separated by a distance h in the z direction. the bottom plate is moving at a velocity u. the incompressible fluid trapped between the plates is moving in the positive x-direction with the bottom plate. align gravity with positive z. assume that the flow is fully-developed and laminar. if the systems operates at steady state and the pressure gradient in x-direction can be ignored, do the following: 1. sketch your system 2. identify the coordinate system to be used. 3. show your coordinates and origin point on the sketch. list all your assumptions. 5. apply the continuity equation to your system. nts of navier stokes equations of choice to your system 7. solve the resulting differential equation to obtain the velocity profile within the system make sure to list your boundary conditions. check units of velocity 8. describe the velocity profile you obtain using engineering terminology. sketch that on the same sketch you provided in (1). 9. obtain the equation that describes the volumetric flow rate in the system. check the units.

What is the stall speed at sea level of an airplane that weights 10000 lbs., has a wing area of 300ft^2, and a maximum lift coefficient of 1.4? what is the stall speed if flaps that double cl,max are applied?