Search results
Results from the WOW.Com Content Network
An altimeter or an altitude meter is an instrument used to measure the altitude of an object above a fixed level. [1] The measurement of altitude is called altimetry , which is related to the term bathymetry , the measurement of depth under water.
In aviation, pressure altitude is the height above a standard datum plane (SDP), which is a theoretical level where the weight of the atmosphere is 29.921 inches of mercury (1,013.2 mbar; 14.696 psi) as measured by a barometer. [2]
On average, a column of air with a cross-sectional area of 1 square centimetre (cm 2), measured from the mean (average) sea level to the top of Earth's atmosphere, has a mass of about 1.03 kilogram and exerts a force or "weight" of about 10.1 newtons, resulting in a pressure of 10.1 N/cm 2 or 101 kN/m 2 (101 kilopascals, kPa).
The greater the altitude, the lower the pressure. When a barometer is supplied with a nonlinear calibration so as to indicate altitude, the instrument is a type of altimeter called a pressure altimeter or barometric altimeter. A pressure altimeter is the altimeter found in most aircraft, and skydivers use wrist-mounted versions for similar ...
where R is the ideal gas constant, T is temperature, M is average molecular weight, and g 0 is the gravitational acceleration at the planet's surface. Using the values T =273 K and M =29 g/mol as characteristic of the Earth's atmosphere, H = RT / Mg = (8.315*273)/(29*9.8) = 7.99, or about 8 km, which coincidentally is approximate height of Mt ...
The average body weight of women in America has been steadily increasing over the past few decades. According to national surveys, about 42 percent of U.S. women have obesity and an additional 27 ...
Macy's earned $28 million, or 10 cents per share, for the three-month period ended Nov. 2. That compares with $41 million, or 15 cents per share in the year-ago period.
PHOTO: Passengers wait in a line for help at the Spirit Airlines ticket counter at the Tampa International Airport, June 1, 2023, in Tampa, Fla. (Chris O'Meara/AP, FILE)