1. The problem statement, all variables and given/known data I was wondering if a glider hits a rubber band bumper is kinetic energy conserved? I can't tell if the data I have supports conservation or loss. I am writing a lab report and data shows that momentum had around a 5% change. Kinetic energy had a 10%-15% change. Momentum is always conserved in a collision so I can conclude its conservered in this case. What is worrying me is that my data is wrong because momentum had a 5% change, I am not sure at what percentage makes it not conserved. I think Kinetic energy is not conserved in this case. Am I right? Mass ~ 0.1833 Velocity Before v1=0.4109 v2=0.4327 v3=0.5959 Velocity After v1= 0.3898 v2= 0.4083 v3= 0.5462 2. Relevant equations K= 1/2*m*v2 p= m*v Percentage of change 1 - (kinetic before/kinetic after) percentage of change momentum 1 - (momentum before/momentum after) 3. The attempt at a solution (.013925671/0.015474070) = .89999 so 90% is conservered a 10% change (0.01527887/0.017159564) = .890 so 89% is conserved a 11% change (0.027342351/0.032544623) = .840 so 86% is conserved a 14% change It seemed that the larger the velocity the more kinetic energy is lost. I am worried my conclusion is completely inaccurate.