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In many engineering uses, the value of "g," the acceleration due to gravity, is taken as a constant. However, g is actually dependent upon the distance from the center of the Earth. A more accurate expression for g is:
Here, g0 is the acceleration of gravity at the surface of the Earth, A is the altitude above the Earth's surface, and Re, is the radius of the Earth, approximately 6,380 kilometers [km]. Assume g0 = 9.8 meters per second squared [m/s2]. What is the value of g at an altitude of 20 miles [mi] in units of meters per second squared (m/s2 )?
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