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Re: a surprising escape speed problem



"Carl E. Mungan" wrote:

I present a simplified version of the problem I have been toying
with. Suppose we get rid of the sun and instead put the earth at the
end of a string (whose length equals the usual earth-sun distance)
and whirl it around so that it matches earth's usual orbital speed of
v_orbit = 29.8 km/s. Also suppose that the earth does not spin on its
axis.

Got it? Okay here's the question: With what speed (relative to the
earth) must you launch a stone so that it just escapes to infinity?


I'm proctoring an exam while I'm writing this - so I can't think through the problem
too deeply. However, how does this differ from an earth moving out in deep space along
a straight line path at 29.8 m/s? The escape speed would still be 11.2 regardless of
the earth's non-accelerated motion. No objects would fly off spontaneously because
they share the earth's linear motion.

Bob at PC

This posting is the position of the writer, not that of SUNY-BSC, NAU or the AAPT.