1. The problem statement, all variables and given/known data A 5850kg truck decelerates uniformly from 85.0km/h to 50.0 km/h. if 95.0% of the energy reduction is converted into heat, how many kilocalories are produced? 2. Relevant equations kinetic energy (Ek)= 1/2mv2 1 Cal= 4.18J 3. The attempt at a solution So first I converted 85.0km/h and 50.0km/h to m/s. 85.0km/h=26.4m/s, 50.0km/h=13.9m/s. Since 26.4m/s is initial velocity and 13.9m/s is final velocity, so the uniform velocity is v1-vo,: 13.9m/s-23.6m/s=-9.7m/s. (Although I'm not quite sure it's right) Then Ek=1/2mv2 .5*(5850kg)(-9.7m/s)2=2.75*105 (.95%)(2.75*105)=2.61*105 so I converted it to cal which 1 cal= 4.18J. so answer came 6.25*104cal. and it was incorrect. someone help me?