Solving Spacetime Homework: Time, Displacement & Clocks

[chevycamaro1987]

Homework Statement

spaceship 3 meters wide, v= 2c/3. (a.) calculate ships time, (b) sq. root factor, (c) Earth's time, (d) ships displacement, (e) lights displacement, and (f) which clock "runs slow"

Homework Equations

a. Ts=(3m)/c
b. square root 1-v^2/c^2
c. Earth's time = answer a/b (it tells me to use the two formulas actually, i figured this is equivalent)
d. ships displacement =vt
e. lights displacement= ct
f. which clock runs slow

The Attempt at a Solution

all of the formula have been given to me, i just want to make sure my answers are right.
a. 3m/3.00X10^8 m/s= 1X10^-8 s
b. sq. root 1-2X10^8= -1.9999999X10^8
c. t= -5X10^-17-----should this be a magnitude?
d. 2c/3*-5X10^-17= -1X10^-8 meters
e. ct= (3.00X10^8 m/s)(-5X10^-17) =-1.5X10^-8
g. i think i remember from the lecture that the Earth clock runs slow because of the displacement, it seems like it takes longer.

like i said, i just want to see if my work is right. i have a feeling c is wrong, because time shouldn't be negative. I am pretty sure the formulas are right because my teacher gave them in the book.

 

[OlderDan]

Your problem statement is a bit vaque to say the least. What times are you talking about? Is 3m is the rest length of the ship?

 

[chevycamaro1987]

Your problem statement is a bit vaque to say the least. What times are you talking about? Is 3m is the rest length of the ship?

I honestly don't know. Everything I was given I put in the problem word for word. But it's ok anyways, I took my final today and this problem wasn't on there, but it is kind of annoying that I can't figure it out.