# Relativistic Mass Formula

1. Jan 21, 2005

### DB

I had some trouble with this question, but I would like to know if for these type of questions, is it safe to say that the velocity of a particle/object is equal to:

$$v=\sqrt{\mid\frac{{m_0}^2}{{X_{m_0}}^2}-1\mid c^2$$

Where $$X$$ is equal to how many times larger it's relativistic mass is compared to it's rest mass.

??? just curious...

PS: \mid represents absolute value, but I think it would also work if:

$$v=\sqrt {-(\frac{{m_0}^2}{{X_{m_0}}^2}-1)c^2}$$

2. Jan 21, 2005

### vincentchan

you do not have a relativity problem, you have an algebra problem... check your algebra

m=m_0 / sqrt (1-(v/c)^2)
v=sqrt(1-(m_o/m)^2)c