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Re: Relationship between Earth Moon



Isaac Newton to the RESCUE ! ! ! ! ! !

While teaching HS physics - I came upon this 'tidbit' some years ago.
I recommend that it become a part of the 'standard' bag of tricks and
trivia for students to be exposed to.

Newton used his new V*V / R formula for circular acceleration to
calculate the acceleration of the moon towards the earth. The
distance to the moon was known to be approximately 60 times the
earth's radius. (Triangulation can get this fairly well)

When he calculated V* V / R for the moon's monthly orbit he was VERY
IMPRESSED by the result.

The moon is accelerating towards the earth at a value that is pretty
dang close to 1/3600 the acceleration of those apples!!!!!


And thus was born the 1/r*r of the Law of Universal Gravitation

At 10:41 AM -0400 on 9/14/01, Herbert H Gottlieb wrote

Although I have been teaching both physics and
earth science for more than 50 years, I just discovered
that I was as ignorant as her students in grasping the
size and distance relationships between the earth and
the moon. Like Tina's students, I had been brainwashed
by faulty diagrams in all of my textbooks and encyclopedias
that all show the earth and the moon less than three earth
diameters apart.

I suggest that all readers of this e-mail do what Tina
suggests in her original e-mail (duplicated below).
Draw an earth-moon diagram on a sheet of notebook paper
with the diameters of the earth and the moon and the
distance between them drawn to scale. Then, based on your
diagram, explain the phases of the moon and the causes of
solar and lunar eclipses.


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Chuck Britton Education is what is left when
britton@ncssm.edu you have forgotten everything
North Carolina School of Science & Math you learned in school.
(919) 286-3366 x224 Albert Einstein, 1936