Question : 1 A loudspeaker is producing sound of a certain wavelength. Which combination of the wavelength (expressed as a multiple of %uo3BBO) and the speakers diameter (expressed as a multiple of DO) would exhibit the greatest amount of diffraction when the sound leaves the speaker and enters the room?
Question : 2 A Camot heat pump is used to heat and maintain a residential building at 75 degrees F. An energy analysis of the house reveals that it loses heat at a rate of 2500 Btu/h per degree F temperature difference between the indoors and the outdoors. For an outdoor temperature of 35 degrees F, determine (a) the coefficient of performance and (b) the required power input to the heat pump.
Question : 3 The car lift at your neighborhood garage is designed such that the radii of the input piston and output plunger are 8.50 x 10-3 m and 0.120 m, respectively. The garage manager likes to use a hydraulic oil in the lift that has a density of 7.80 x 102 kg/m3. Compared to the weight of the output plunger, the weight of the input piston is negligible. Determine the force Fi needed at the input piston in order to support the 12,000-N combined weight of a car and the output plunger under the following conditions.
The bottom surfaces of the input piston and output plunger are at the same level. ____________N
The bottom surface of the input piston is 2.80 m below that of the output plunger. ____________N