If an object with a mass of # 3kg # changes speed from #4m/s# to # 9m/s#, by how much does its kinetic energy change?

1 Answer
Feb 20, 2017

Answer:

The kinetic energy will increase from 24 J to 121.5 J, an increase of 97.5 J.

Explanation:

Because kinetic energy is given by #1/2mv^2# regardless of the particular situation involved, the change in kinetic energy here will be

#DeltaK = 1/2mv_f^2-1/2mv_i^2 = 1/2 (3)(9)^2-1/2(3)(4)^2#

#DeltaK = 121.5 J - 24 J = 97.5 J#