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. Click Here to return to the search form.
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