Physics 12-23/02/10

Special Relativity

Light is constant (in vacuum) so space(distance) and time must be relative.
This leads to pain-in-the-ass concepts such as time dilation, length dilation and mass dilation.

Time Dilation

................to
......-----------------
tv =..__________
......./....( V^2 )
....../.(1- -----)
....\/......( c^2 )

(ignore the dots)

Where 'to' is time measured by the thing moving close to light speed (or stationary relative to on board time)
Where 'tv' is time measured by the guy outside the thing moving close to light speed (the position that can measure the velocity of the thing)

Note: since nothing can go over the speed of light, tv is always BIGGER than to


Space (length) dilation

...................__________
................. /....( V^2 )
Lv = Lo x .../.(1- -----)
..............\/......( c^2 )

(ignore the dots)

Where 'Lo' is the length measured inside the moving thing (stationary relative to object)
Where 'Lv' is the length measured OUTSIDE the moving thing (moving relative to object)

Note: Since nothing can go over the speed of light, Lv is always SMALLER than Lo


Mass Dilation

................Mo
......-----------------
Mv =..__________
......./....( V^2 )
....../.(1- -----)
....\/......( c^2 )

(ignore the dots)

Where 'Mo' is the Mass measured inside the moving thing (stationary relative to object)
Where 'Mv' is the mass measured OUTSIDE the moving thing (moving relative to object)

Note: Since nothing can go over the speed of light, Mv is always LARGER than Mo

Random Info.

It takes 118.10.... days to reach speed of light if going 3 G's.
It takes 354.something days to reach the speed of light if going 1 G
Time dilation makes time travel forwards possible.
The twin paradox is incorrect due to one thing being non-inertial reference frame and proved with general relativity.
Time travel backwards is impossible.
Even the effect of gravity travels no more than the speed of light o_O
You need a hell of a lot of energy to make something go close to the speed of light since some of the energy gets converted to mass ... or momentum ...

The closer you get to a large gravitational mass the more time gets dilated also (YOU DO NOT NEED TO KNOW THIS , IN FACT YOU SHOULDN'T)
Actually screw this i might as well put something up.

Gravitational Time Dilation (General Relativity)

The lower the gravitational potential energy an object has, the more its time gets dilated.
I dont know the formula for it and i reckon it would just confuse everyone anyway ... maybe except for ishraq.




That is all.
I hate tv/Lv and to/Lo -__- i keep getting them confused (Mv & Mo too).

That is really all.