simultaneity (1 Viewer)

[KFunk]

Read it as defined by the master:

Relativity: The Special and General Theory

Specifically:

The Relativity of Simultaneity

 

[table for 1]

sorry i took so long to reply, i needed a break from physics, well, from school altogether.

to zeropoint: thanks for being so patient with me, and helping me to understand simutaneity !! i get simutaneity, but yeah, i'll just cut out the doors. -.-" i have a feeling i'm going to be coming here soon with more annoying questions...

to KFunk: thanks for the website, it explains wanton-wonton's example in more detail, i'm sure i'll need the site as a reference ! =D

 

[wanton-wonton]

Read it as defined by the master:

Relativity: The Special and General Theory

Specifically:

The Relativity of Simultaneity

Your signature is funky.

 

[AntiHyper]

How about if there's a "moving tunnel" in space that's travelling near the speed of light in the direction of 'x'.
And a vehicle travels in the tunnel near the speed of light in respect to the tunnel in the direction of 'x'.
What speed will it have as it leaves the tunnel?

I'd say physically it'd move faster than light but it can't gauge its speed by looking at its surroundings. Instead the people in the vehicle would see 'the moon' to be somewhat cookie sized thickness. By doing this the world 'becomes' a smaller place so that anyone always 'judge' speed to be below the speed of light.

 

[KFunk]

Thank you Wanton, it is intended to be a most truly funky signature.


AntiHyper, you're thinking in terms of newtonian non-relativistic mechanics there. You need to use the formulas of special relativity when calculating relative velocities at such high speeds. To quote a website:
( http://math.ucr.edu/home/baez/physics/Relativity/SR/velocity.html )




Suppose an object A is moving with a velocity v relative to an object B and B is moving with a velocity u (in the same direction) relative to an object C. What is the velocity of A relative to C?
v
u -------> A
-------> B


In non-relativistic mechanics the velocities are simply added and the answer is that A is moving with a velocity w = u+v relative to C. But in special relativity the velocities must be combined using the formula

w = (u + v)/(1 + uv/c2)

 

[wanton-wonton]

How about if there's a "moving tunnel" in space that's travelling near the speed of light in the direction of 'x'.
And a vehicle travels in the tunnel near the speed of light in respect to the tunnel in the direction of 'x'.
What speed will it have as it leaves the tunnel?

I'd say physically it'd move faster than light but it can't gauge its speed by looking at its surroundings. Instead the people in the vehicle would see 'the moon' to be somewhat cookie sized thickness. By doing this the world 'becomes' a smaller place so that anyone always 'judge' speed to be below the speed of light.

I don't know what you're talking about, but when referring to relative velocity of high velocities, e.g. near the speed of light, you use the equation as follows:

combined velocity = (v1 + v2)/(1+v1v2/c^2)

E.g., if a space ship is travelling at 0.9 towards another space ship also travelling at 0.9c, the relative speed of one space ship to another is not 1.8 c, instead, use the equation.

You might've missed it....Same as KFUNK's post basically.

 

[Xayma]

You need to question things if you are to understand them, if we didn't question things we would still be in the stone age.

Also note that post had been answered, nearly a month ago.

 

[pinto]

hi, i understand all the thought experiments and why they work, however if you were to ask me "What is the principle of relativity?" or "what is special relativity?" or "what is the relativity of simultaneity"i couldnt answer, i could only give examples. could someone please help me with a defn of each?

 

[davo_]

I can say you won't get a question directly asking you that... And you can't really answer "what is the theory of relativity?" with a simple statement- to describe what you need to know about the theory just try to know your dot points and you should be fine.

 

[KFunk]

You'd probably be best off citing the central postulates of relativity then giving a couple of their implications.

1. First postulate (principle of relativity)

The laws of the universe are the same regardless of inertial frame of reference.

2. Second postulate (invariance of c)

The speed of light in vacuum is the same to all inertial observers, is the same in all directions, and does not depend on the velocity of the object emitting the light.

From these basic principles of relativity you can derive all the √(1 - v²/c²) equations that you use.