How Does Velocity Affect Mass in Relativity?

[iaberrant]

Homework Statement

On Earth a man weights 78kg. what is his weight on a starship which is traveling at 0.93c?

Homework Equations

Are the following correct for mass change in terms of relativity?

mr = E/c2
m0 = sqrt(E2/c4 - p2/c2)

Where E is energy, p is momentum and c is the speed of light in vacuum

Need help solving this!
Thank you in advance!

 

[jrlaguna]

Are you sure the problem is stated as weight? Because, if it is, then the solution is pretty simple...

If it says "mass", then we can do more... :)

 

[iaberrant]

yes it states weight and i think i have an idea of how to do it using the formula
M= Mo / [√ 1 - v^2/ c^2]
where Mo is 78kg and velocity is 0.93c
M= 78 / [√ 1 - (0.93c^2)^2/ c^2]
M= 78 / [√ 1 - 0.93c^2]
M=212.2105291kg

So the weight would be approximately 212.2 kg

is this correct working and answer?

thank you in advance~!

s