The relativity of time: time dilation

AI Thread Summary
In this discussion, two questions regarding time dilation are posed. The first question involves calculating the time recorded on Earth for a race monitored by a spaceship traveling at 0.900c, where the time measured by the spaceship is 125.6 seconds. The second question asks how the speed of a spacecraft at 0.850c affects the number of hours in an Earth day, depending on whether it is moving towards or away from Earth. Participants clarify that events on Earth appear to happen faster from the spaceship's perspective and that the effects of redshift and blueshift must be considered in these calculations. The conversation emphasizes the importance of understanding the relativity of time in different frames of reference.
Jbum
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QUESTION #1:

1. suppose a race on Earth was monitored by a spaceship traveling in space at 0.900c relative to the Earth and the space travelers measured the time of the race to be 125.6s. What was the time recorded on earth?

2. t = gamma t' where gamma = 1/ sqrt(1-v squared/c squared)

3. v = 0.900c
t = 125.6s??
t' = ?

I stopped here because I am not sure if I have my ts right. I know how to do all the math, just figuring out which t is which is harder for me in this particular question.

QUESTION #2

1. spacecraft is passing through the solar system at speed of 0.850c relative to earth. what does the captain measure for the number of hours in an Earth day if the spacecraft is moving a) towards Earth and b) away from earth?

2. v = 0.850c
t =?
t' = ?

3. No idea. How does traveling towards or away from Earth affect the number of Earth hours that one measures? that, i do not understand.thanks for the help in advance.
 
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Jbum said:
QUESTION #1:

1. suppose a race on Earth was monitored by a spaceship traveling in space at 0.900c relative to the Earth and the space travelers measured the time of the race to be 125.6s. What was the time recorded on earth?

2. t = gamma t' where gamma = 1/ sqrt(1-v squared/c squared)

3. v = 0.900c
t = 125.6s??
t' = ?

I stopped here because I am not sure if I have my ts right. I know how to do all the math, just figuring out which t is which is harder for me in this particular question.




QUESTION #2

1. spacecraft is passing through the solar system at speed of 0.850c relative to earth. what does the captain measure for the number of hours in an Earth day if the spacecraft is moving a) towards Earth and b) away from earth?

2. v = 0.850c
t =?
t' = ?

3. No idea. How does traveling towards or away from Earth affect the number of Earth hours that one measures? that, i do not understand.


thanks for the help in advance.

Don't put two unrelated question under the same thread...i.e. start a new one for new questions.
 
yes, i am aware of that thanks. i just happened to accidentally post it in the same thread, but did not know how to remove it.
 
They're both time dilation questions, I'd rather not see two topics pertaining to the same concept myself >_>

Keep in mind that on the spaceship in both cases, events on Earth would appear to be happening faster

No idea. How does traveling towards or away from Earth affect the number of Earth hours that one measures?

Does the previous problem even mention if it's going away or towards, or just "relative to"? Did that make a difference?
 
blochwave said:
They're both time dilation questions, I'd rather not see two topics pertaining to the same concept myself >_>


Orignially the post was inside another unrelated topic, hence my comment above. These two question are related but the thread has already be split out by a mentor.
 
They would observe time of Earth's rotations as 24 hours long from either direction because they would have compensated for the redshift/blueshift in their computations.
 
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