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If you were traveling at the speed of Earth and
heading in the opposite direction of Earth's
rotation, what would happen to time?
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Question Date: 2006-01-20 | | Answer 1:
The Earth is not moving any near fast enough for
the effects of time dilation and special
relativity to have an effect. Objects in the Solar
System generally speaking are moving with respect
to each-other at tens of kilometers per second,
and the speed of light is three-hundred thousand
kilometers per second. You need to be going a
significant fraction of the speed of light for
time dilation to be important. It is of course in
effect at any speed, but it is (almost) not
measurable.
What would happen if you were
going fast enough for time dilation to be
important? You would not notice anything until you
looked out the window of your spaceship. Then you
would notice that everything else would be moving
more slowly, compared to you. That is why the
theory is called relativity: it is how fast things
are going relative to you that matters. There is
no fundamental state of "not moving", and the
speed of light in all directions is the same, no
matter how you are moving.
How can things
be slow on Earth and not for you, when I (on
Earth) think that you are going slowly and I am
not? This is called the Twin Paradox, and it stems
from the fact that in order for us to truly
compare how fast time is traveling for each of us,
we must be not moving with respect to each-other,
and then be moving with respect to each-other.
This means that acceleration must take place,
since one of us has to go from one state of motion
to another. Special relativity only functions if
there is no acceleration (actually, if you break
the acceleration into discontinuous jumps, you can
still do it, but the algebra gets really intense).
For real-world problems of accelerating systems,
you need general relativity.I do not have the
understanding of mathematics to be able to explain
general relativity to you. | | Answer 2:
Nothing! Time does not depend on the rotation of
the Earth. Yes it is true that we set our clocks
to the Earths rotation but that's just a matter of
convenience. Time itself is more fundamental. | | Answer 3:
Well, the short answer is that nothing much would
happen. The Earth rotates at a rate about 1000
miles per hour which is faster than the speed of
sound but not really by a lot. So traveling this
speed would be like flying in a fighter jet which
military pilots do all the time. By the way, the
space shuttle travels at about 17,000 miles per
hour.The Earth travels around the Sun at a faster
rate - about67,000 miles per hour by my
calculations - but still much slower than the
speed of light which is 186,000 miles per second! | | Answer 4:
This is a great question. If you were traveling
the same speed as the earth and heading in the
opposite direction, then for you, day and night
would cease to exist as the 24-hour cycles that we
are familiar with. Instead, you would remain in
the same position relative to the sun and
experience the same time of day (or night)
perpetually without ever seeing the repeated cycle
of sunrise,day, sunset, and night. However, time
is a different concept than day and night. We
think of time only in terms of day and night
because the two are related for anybody living on
Earth and turning with the planet. But this
relationship between time and the day and night
caused by Earth's rotation ends as soon as you
leave the planet's rotational frame of reference.
As an example,have you ever flown in a plane from
east to west, especially at sunset? It appears
that the sunset almost freezes and takes forever
to finish, almost as if time were to slow down.
This is because your position relative to the sun
is changing very slowly because you are traveling
in the opposite direction of earth's rotation and
effectively "chasing the sun". However, time does
not slow down either for you or the people on
Earth who the pilots are communicating with. Time
would not stop as it always continues in the same
manner.
However, whenever you speed up
relative to someone else, you would experience
time at a negligibly different rate than people
below on Earth, due to Einstein's theory of
special relativity. This concept is called "time
dilation" and occurs because the speed of light is
constant regardless of your frame of reference.
In order for the speed of an external object
(light) to be the same for two things moving at
different velocities relative to that object,time
must slow down for the object that is moving
faster away from the source of the light and time
must speed up for the object that is moving faster
towards the source of light. This is because
velocity equals distance divided by time. When
you move away from a source of light, you are
essentially increasing the distance that the light
travels to get to you. In order for the velocity
of light to remain constant, you must also
increase the number of seconds that it takes the
light to travel that distance. Conversely, if you
move towards a source of light, you are decreasing
the distance the light travels to get to you. To
keep the velocity of light constant from your
frame of reference, you must also decrease the
number of seconds that it takes the light to
travel that distance.
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