How Fast is the Rocket Traveling According to Earth's Time Reference?

In summary, the conversation discussed a problem involving length contraction and time dilation. The given information included the distance of a star from Earth, the time it took for a rocket to reach the star, and the fact that there was no acceleration involved. The problem involved finding the velocity of the rocket in Earth's reference frame. Equations involving time, length, and the Lorentz factor were mentioned, but it was unclear how to use them with the given information. There was also a discussion about calculating the time passed in Earth's reference frame, but it was uncertain how to do so without knowing the velocity of the rocket. The conversation ended with the suggestion to use the equation vearth=dearth/tearth and to plug and ch
  • #1
PsychonautQQ
784
10

Homework Statement


A star is 27c*y away from the rest reference of earth. A rocket reaches star A from Earth and according to clocks on it 12 hours have passed. How fast is the rocket traveling in Earth's reference frame?


Homework Equations


tpγ=t
Lp/γ=L


The Attempt at a Solution


The problem is under the category of length contraction and time dilation so I assume these are the two equations I must use. However when trying to do the problem I only was given t and Lp, and yet there are three variables (tp, L, and v). Help ;-(
 
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  • #2
Can you calculate what time has passed wrt IRearth?
(I am assuming Earth is assumed to be an IR and the ship doesn't accelerate.)
 
  • #3
yes, no acceleration.
I don't think I can calculate the time wrt IRearth..? I would need to know the velocity to do that so I knew the gamma factor correct?
 
  • #4
vearth=dearth/tearth
tearth=dearth/vearth
plug and chug.
 
  • #5
I don't know t_earth though? I only know it took 12 years from the spaceships frame..? oh... is Vearth 27c*y / 12 years...? I'm a noob X_X
 
  • #6
but that's not REALLY the speed Earth see's it moving is it? Because Earth couldn't see the rocket traveling faster than C could it?
 
  • #7
Enigman said:
vearth=dearth/tearth
tearth=dearth/vearth
plug and chug.

tearthγ=t
or, tearth=t/γ
equate the tearth
Quadratic eq in v2*earth
*editted
 
Last edited:

1. What is the theory of Special Relativity?

The theory of Special Relativity is a fundamental theory in physics that describes the relationship between space and time. It was developed by Albert Einstein in 1905 and is based on two main principles: the principle of relativity and the principle of the constancy of the speed of light.

2. What does the theory of Special Relativity say about the speed of light?

The theory of Special Relativity states that the speed of light in a vacuum is constant and is the same for all observers, regardless of their relative motion. This means that the speed of light is the ultimate speed limit in the universe, and nothing can travel faster than it.

3. How does Special Relativity affect our understanding of time and space?

Special Relativity introduces the concept of spacetime, which combines the three dimensions of space with the dimension of time. It also shows that time and space are relative and can be affected by an observer's motion. This means that different observers can experience time and space differently depending on their relative motion.

4. Can Special Relativity be applied in everyday life?

Yes, Special Relativity has been proven to be an accurate theory and is used in many practical applications, such as GPS technology, particle accelerators, and nuclear power plants. However, its effects are only noticeable at very high speeds or in extreme gravitational fields, so we don't experience them in our everyday lives.

5. How does Special Relativity relate to General Relativity?

Special Relativity is a special case of General Relativity, which is a more comprehensive theory of gravity that takes into account the effects of acceleration and gravity on the curvature of spacetime. Special Relativity only applies to inertial frames of reference, while General Relativity can be applied to any frame of reference, including accelerating ones.

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