Answer 1:
Actually, it sounds like you're talking about
a rotating black hole, also called a Kerr black
hole. Kerr black holes are described by two
numbers: the mass of the black hole, and
something we call its angular momentum
(basically, how fast the black hole
is "spinning"). Now, there are two effects that
describe how an object falls into a Kerr black
hole: there's the usual gravitational pull from
the black hole's mass, but there's also an
effect from the black hole's rotation. It turns
out that if an object is falling into the black
hole while rotating in the same direction as the
black hole, the object is "repelled," so that it
falls in more slowly. If instead an object
falls into the black hole while rotating in the
opposite direction as the black hole, the object
is "attracted," so it falls in more quickly.
So, what you call the "spinning force" (which is
more correctly called a "centrifugal force") can
either make objects fall in more quickly or more
slowly, depending on how they fall into the
black hole.
Unfortunately, black holes are incredibly
massive things, so we can't create them in a lab
to perform experiments on them. Everything we
know about them comes from either studying
Einstein's theory of gravity, which is what
predicts their existence, or observing black
holes that are far away (usually, the types of
black holes we can observe are large black holes
that are feeding at the center of far-away
galaxies, in which case they're
called "quasars"). So, it's very difficult to
test your hypothesis with an experiment. The
best we can do is to look at Einstein's
equations of gravity and see what they tell us
about the way a black hole behaves, and that's
how we know everything I said above about
something either falling in faster or slower,
depending on which way it falls in.
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Answer 2:
This is not a good science fair project
because it's impossible for you to test. You
would need a black hole to test it, and there
are no black holes available on or near the
Earth, even in a laboratory. The only black
holes we know about are all many light years
away, and the only way we know about them is we
observe the effects of their gravity on stars
and other objects which tells us that there is
an extremely small, extremely massive object
that really cannot be anything except for a
black hole.
According to Einstein's theory of general
relativity, which is currently the best theory
we have that describes black holes (as well as
the rest of gravity), anything that has mass
exerts a force that causes space to fall inward
into them, and this inward flow of space creates
the force that we call gravity: objects are
pulled in with the space that they sit in. At
the event horizon of a black hole, the speed of
space falling in equals the speed of light,
which means that nothing can escape, since
nothing can move in space any faster than the
speed of light. However, the speed of the infall
of space continues to increase toward the center
of a black hole, reaching infinity at a central
point inside of the black hole called a
singularity. Mathematically, the equations of
general relativity require you to divide by zero
at the singularity, which means that this is
where the theory breaks down and we don't know
what happens.
Black holes don't need to spin, but because
spinning matter falling into a black hole can't
stop spinning (another law of physics),
virtually all black holes in nature do spin. A
spinning black hole, or for that matter any
object with mass, causes the flow of space to
not only fall inward, but to spiral inward, like
a whirlpool. This means that an object falling
into a spinning black hole, even if it is diving
straight for the singularity, will actually
spiral in, because it will get caught in the
swirl of space as it falls in. The same thing
happens as I said with any massive body: if you
drop a pencil from your hand, it will start a
very steep spiral toward the center of the Earth
as it falls before it hits the ground, because
the Earth is spinning. The Earth just isn't
massive enough or spinning fast enough for you
to notice the difference from a straight fall
downward.
Spinning black holes also have some other odd
characteristics - the central singularity of a
spinning black hole is ring-shaped, for example,
not a point. I am not enough of a physicist to
explain to you how this works.
Galaxies, meanwhile, do not spin because of
the spinning black hole in the center. Galaxies
spin for the same reason that the Earth spins:
you can't stop spinning unless you have
something to stop you. This is true even if you
are spinning in a chair, say - you slow down and
stop because of friction with the joint in the
base of the chair. If it weren't for friction
and you were spinning, you would continue
spinning forever.
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