1. A 1100 kg car at rest at the top of a hill accelerates down the road, reaching a speed of 20 m/s after descending a height of 120 m. What was its total change in mechanical energy (KE plus PEG) as of that moment in Megajoules? 2.KE = 1/2 mv^2 and PEg = mgh 3. I used the above formulas to figure out KE = 2.20E5 and PEg = 1.3E6. When I add both together, I get 1.51E6 and convert it to MJ = 1.51MJ. When I put in the answer, this is incorrect. Am I missing something?