# Just when I started to get things straught in my head.

#### bm0p700f

http://www.fourmilab.ch/cship/timedial.html

Gives a formula for time dialation which is repeated in many other soucres. In this version t'/to increases with v. Its time dilation time is meant to slow?

http://www.phys.unsw.edu.au/einsteinlight/jw/module4_time_dilation.htm

A useful set of pages for those wanting to learn. The derivation for time dilation is in the form I am familiar with as v increas t'/to decreases, time dilation I understand. Two different equations for the same thing cannot be right?

I don't solve problems with SR, I have never needed to but still I try to undersand. Can someone help resolve this apparant problem.

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#### sylas

http://www.fourmilab.ch/cship/timedial.html

Gives a formula for time dialation which is repeated in many other soucres. In this version t'/to increases with v. Its time dilation time is meant to slow?

http://www.phys.unsw.edu.au/einsteinlight/jw/module4_time_dilation.htm

A useful set of pages for those wanting to learn. The derivation for time dilation is in the form I am familiar with as v increas t'/to decreases, time dilation I understand. Two different equations for the same thing cannot be right?

I don't solve problems with SR, I have never needed to but still I try to undersand. Can someone help resolve this apparant problem.
They are both using the same formula, but different conventions for variable names. In the first page t' is the time on the moving ship for a stationary observer, and t is the observer's own time.

On the second page, T is the time of a tick on Zoe's clock as Jasper observes it, and T' is the time of a tick on the same clock, as Zoe sees it herself.

Thus the prime is used differently on the two pages. In the first page t' is time on a clock moving wrt to the observer; and on the second T' is the time on the observer's own clock.

Cheers -- sylas

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