What is the Kinetic Energy of Bullets Fired at Different Speeds?

[PepeF.]

Homework Statement

two 3.5g bullets are fired with speeds of 42.4 m/s and the 2nd one with 69.6 m/s

what is the kinetic energy of the first bullet?
the second one?

Homework Equations

EK=(1/2)mv^2

The Attempt at a Solution

EK=(1/2)3.6*42.4^2 = 3235.968

it is wrong.. why?

 

[mgb_phys]

units

 

[JakePearson]

you have not converted the mass of the bullet from grams to kgrams

0.50 x (3.5x10^-3) x 42.4^2 = 3.14J

this is the answer i got