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I have a problem from my modern physic class I'm hoping to get some insight on... I got an answer, but it seems, well, odd...

Inertial frame S' moves with speed v=[tex]\frac{3c}{5}[/tex] in the +xdirextion past inertial frameS. Event A is a synchronizing event. Event B occurs at t=0 in Frame S and at position x'=1 meter in frame S'. Given:

For Event A:

[tex]x_{A}=0[/tex]

[tex]x_{A}'=0[/tex]

[tex]t_{A}=0[/tex]

[tex]t_{A}'=0[/tex]

For Event B:

[tex]x_{B}'=1 meter[/tex]

[tex]t_{B}=0[/tex]

Find,

[tex]x_{B}[/tex] and [tex]t_{B}[/tex]'

The relevent equations are the two lorentz transforms:

[tex]x'=\gamma(x-vt)[/tex]

and

[tex]t=\gamma(t'+\frac{vx'}{c/^{2}}[/tex]

For [tex]x_{B}[/tex]:

Applying equation 1 I get,

[tex]\frac{x'}{\gamma}+vt=x[/tex]

Then [tex]x=\frac{4}{5} meters[/tex]

and for [tex]t_{B}[/tex]' I get (applying equation 2),

[tex]t'=\frac{t}{\gamma}-\frac{vx'}{c^{2}}=-2.001 x 10^{-9} seconds[/tex]

I'm confused about the second answer. Did I do something wrong? or does this just mean that in frame S' the event happens [tex]-2.001 x 10^{-9}[/tex] seconds prior to t=0 in frame S?

Heeeeeeeelp please!

## Homework Statement

Inertial frame S' moves with speed v=[tex]\frac{3c}{5}[/tex] in the +xdirextion past inertial frameS. Event A is a synchronizing event. Event B occurs at t=0 in Frame S and at position x'=1 meter in frame S'. Given:

For Event A:

[tex]x_{A}=0[/tex]

[tex]x_{A}'=0[/tex]

[tex]t_{A}=0[/tex]

[tex]t_{A}'=0[/tex]

For Event B:

[tex]x_{B}'=1 meter[/tex]

[tex]t_{B}=0[/tex]

Find,

[tex]x_{B}[/tex] and [tex]t_{B}[/tex]'

## Homework Equations

The relevent equations are the two lorentz transforms:

[tex]x'=\gamma(x-vt)[/tex]

and

[tex]t=\gamma(t'+\frac{vx'}{c/^{2}}[/tex]

## The Attempt at a Solution

For [tex]x_{B}[/tex]:

Applying equation 1 I get,

[tex]\frac{x'}{\gamma}+vt=x[/tex]

Then [tex]x=\frac{4}{5} meters[/tex]

and for [tex]t_{B}[/tex]' I get (applying equation 2),

[tex]t'=\frac{t}{\gamma}-\frac{vx'}{c^{2}}=-2.001 x 10^{-9} seconds[/tex]

I'm confused about the second answer. Did I do something wrong? or does this just mean that in frame S' the event happens [tex]-2.001 x 10^{-9}[/tex] seconds prior to t=0 in frame S?

Heeeeeeeelp please!

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