How Do You Calculate Velocity from Kinetic Energy?

[curiousgeorge99]

Homework Statement

A molecule has mass 5.3 x 10^-26 Kg and KE 6.24 x10^-21. What is the velocity in m/s?

Homework Equations

KE = mv^2 / 2

The Attempt at a Solution

I plug the numbers into the equation and get an answer of 15.34, but the correct answer is 48.6 m/s. Is this the wrong equation?

 

[neutrino]

That is the correct equation.

If that's the KE in Joules, the answer seems closer to 486m/s.
http://www.google.com/search?hl=en&...hs=kTh&q=sqrt(2*6.24e-21/5.3e-26)&btnG=Search

 

[esalihm]

check ur units. that's the correct equation to use
and I get 485 too