1. The problem statement, all variables and given/known data A crate of mass 9.6 kg is pulled up a rough incline with an initial speed of 1.44 m/s. The pulling force is 92 N parallel to the incline, which makes an angle of 19.4° with the horizontal. The coefficient of kinetic friction is 0.400, and the crate is pulled 4.92 m. (d) What is the change in kinetic energy of the crate? 2. Relevant equations Kei = 1/2mv2 3. The attempt at a solution [m(u)^2] / 2 K.E (i) = [9.6(1.44)^2 ] / 2 K.E (i) = 9.95 J I understand this much is correct. But when and why do I use integrals. I understand it calculates the area under the equation giving me the total amount of work. What I don't understand is, when's the proper time to use it. Are there key words to look out for or...??