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Unit 7: Astrophysics Page 47
That’s ridiculous! If there was no out in deep space (clear of any
gravity in space, wouldn’t the gravitational influences). They
moon go veering off in a straight would be indistinguishable.
line? Wouldn’t the planets stop
You’d know eventually you were
orbiting the sun?
freefalling on Earth because you’d
Sometimes you’ll also see words to smack into the ground and large
the effect of: “You need to be free forces would let you know you
of the Earth’s gravitational pull to were not in deep space.
experience weightlessness.”
The astronaut in the space shuttle
Another ridiculous statement. You is in exactly the same situation of
can experience freefall right here freefall as you were and therefore
on Earth. Just go into an elevator didn’t feel gravity.
to the top floor and cut the cord.
General Relativity came years after
You’ll be in freefall in a very short
Special Relativity, as Einstein had
amount of time.
to rearrange physics a bit in order
to made sense of everything.
This is one of the very few theories
which was not developed by the
works of preceding scientists.
Einstein came up with this all on
his own in the laboratory of his
mind by simply asking questions.
Although a hundred years old,
General Relativity is not nearly as
If while in this freefalling elevator well-tested as Special Relativity.
you took a ball out of your pocket
Scientists know that Special
and let it go, you’d see that it falls
Relativity is a proven fact, but they
with the same acceleration that
are only mostly sure about General
you do and will appear ‘weightless’.
Relativity.
General Relativity It’s incredible to think that one
General Relativity states that you man’s ideas nearly a century ago
would not be able to tell if you are still unable to be fully tested
were freefalling in an elevator with today due to lack of technology.
the cord cut or in an elevator box Einstein was able to expect the
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