Ratio of kinetic to rest energy for a baseball at 44 m/s

[MillerGenuine]

Homework Statement

A pitcher can throw a baseball at 44 m/s. what is the ratio of kinetic energy to the rest energy E=mc^2. (can you use k=1/2mv^2 ?)

Homework Equations

rest energy=mc^2
K=gamma*mc^2 - mc^2
k=1/2mv^2

The Attempt at a Solution

I am just not sure how to go about this problem. It seems i can use k=1/2mv^2 because the velocity is well below c. From there i would take me kinetic energy and divide it by the rest enregy to get the ratio..??

 

[berkeman]

Homework Statement

A pitcher can throw a baseball at 44 m/s. what is the ratio of kinetic energy to the rest energy E=mc^2. (can you use k=1/2mv^2 ?)

Homework Equations

rest energy=mc^2
K=gamma*mc^2 - mc^2
k=1/2mv^2

The Attempt at a Solution

I am just not sure how to go about this problem. It seems i can use k=1/2mv^2 because the velocity is well below c. From there i would take me kinetic energy and divide it by the rest enregy to get the ratio..??

Yep. They just want to show how huge the rest energy is...