Okay here is my question.:shy: If Total Energy should be constant, because the loss in Potention energy should equal a gain in Kinetic Energy, where does the missing total energy go to ? Here is my data; TOTAL ENERGY: MISSING ENERGY: .1254 .00132 .1236 .00103 .1239 .00106 .11883 .0062 .1241 .00085 .1049 .02007 .12254 .00246 .1189 .00608 .1153 .00961 .1191 .00586 .10509 .0191 To obtain my missing energy I took the highess total energy which is the top of the pattern, .1254 MINUS the other results to obtain my missing energy. DESCRIPTION: In our lab we used a ball and let it accelerate down a slope that starts high, goes DOWN and back UP with a smaller height and goes back down. MY question is: If Total Energy should be constant, because the loss in Potention energy should equal a gain in Kinetic Energy, where does the missing total energy go to ? HERE is some hints that our teacher gave us to get through the question A) Where is the ball missing the least amount of energy? Why ? B) How else is the ball using energy ? C) If friction only creates heat in kinetic mode does friction created heat account for the missing energy ? D) Is the ball missing more and more energy from one end of the track to the other how can it get energy back once its gone ? Really hope you can help, if you need further data just let me know I can provide some more including the height from which we drop the ball from, the balls mass, speed and time through photogates from the stop. Thank you.