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I’m confused. Does this math check out?

Circumference is 24,901 - so about 1000 mph at equator.

1000 mph / 3600 s / h = 0.27 mps

0.27 * (1/250) = 0.001 miles?

Doing this math on my phone but am I missing something here?




You are correct. Using GNU units:

    $ units '2 * pi * earthradius / day * (second / 250)' 
        Definition: 1.8532517 m
Which is 0.0011515572 miles...


I think the parent comment was confusing/misremembering the rotational speed value in miles per hour as miles per second.


Even if we stretch out and look at how fast the Earth orbits the sun, it still doesn't explain the 4 mile figure.

Earth's orbital speed: 66,200 mph

66,200 mph / 3600 s/h = 18.38 mps

18.38 * (1/250) = 0.07 miles


I got the same answer


I think it's relative and phrased poorly, since the orbiter has to circle the earth at a certain faster speed. But quick googling shows Apollo 8 was traveling about a mile a second?




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