Posted by Skyler on .
As a block of wood with the mass of 2.00 kg slides along a floor, it's speed decreases from 4.0 m/s to 1.0 m/s. How much kinetic energy does it lose?

Physics 
Raf,
Kinetic energy is defined with
K = 1/2*m*v^2
so you have Kf  Ki
[1/2(m)(vf)^2]  [1/2(m)(vi)^2] =
m = mass
v = velocity; f for final, i for initial
your answer will be in kg * m/s^2
which is the developed way of writing Newtons because 1 kg * m/s^2 = 1 N