The noise criteria (NC) rating system used to rate the sound levels of registers and grilles is:
A) A subjective scale ranking registers from 1—10.
B) Based on graphical analysis of standing pressure waves.
C) The average decibel reading of five specific frequencies of sound.
D) The decibel reading at a frequency of 1,500 Hz.
D
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The intensive health practices necessary to maintain a successful operation in cattle ranching or dairy farming provide few job opportunities in animal welfare
Indicate whether the statement is true or false
HVAC Excellence:
A) Established an organization to provide programmatic accreditation for HVAC programs. B) Provides a list of mechanical manufacturing codes for the HVAC industry. C) Oversees national curriculum standards for all trade and technical education organizations. D) Regulates all HVACR manufacturing facilities in the United States.
How many motor designs does NEMA designate?
a. 2 b. 5 c. 7 d. 10
Chinook, a military helicopter has two three-blade rotor systems, each turning in opposite direction. Each blade has a diameter of approximately 41 ft. The blades can spin at angular speeds of up to 225 rpm. Determine the translational speed of a particle located at the tip of a blade. Express your answer in ft/s, mph, m/s, and km/h.
What will be an ideal response?