I've always wondered just how inertial (i.e. non-accelerating) various reference frames are. Yesterday I finally sat down and did the math. Some of the relative magnitudes surprised me. Here we go -- comparing accelerations (rough values):
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9.81 m/s^2: acceleration of object in freefall at Earth's surface 8.68 m/s^2: accel of @Space_Station center of mass 1.63 m/s^2: accel of object in freefall at Moon's surface 0.034 m/s^2: centripetal accel at equator (makes you slightly lighter) due to Earth's rotation
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I’m curious... do you have data on acceleration of object in free fall at sea level vs. say... mt Everest?
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Replying to @fbarton @spasmunkey @Space_Station
Great question. g falls off with the square of distance, so for Everest, which is about 0.0014 Earth radii in height, the falloff will be 0.0028g, or about 0.027 m/s^2. That's similar in magnitude to the effect of Earth's rotation. Earth's equatorial bulge plays a similar role.

Feb 8, 2019 · 9:41 PM UTC
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