Title: Conservation of Energy LabPurpose: To verify that the total energy of an object doesn't change if the object hasn't done work.Procedure:1. Attach a photo gate to the bottom of the tube that is attached to a vertical metal rod.2. Attach the photo gate to the computer, and open Mac Motion.3. Record all measurements, tube to ground, tube to photo gate.4. Go get a small piece of PVC pipe that will be dropped through the tube5. Measure both mass and length of the small piece of PVC pipe.6. Drop the small piece of PVC pipe through the long piece of pipe and through the photo gate7. Record the amount of time it took for the small piece of PVC p ...view middle of the document...
PE=mgh=(.0116kg)(9.81N/kg)(1.876m)=0.212JKE=1/2mv"=0JTE=PE+KE=0.212J+0J=0.212JCalculating the Average Speed of the object as it passes through the photo gate..0115s+.0116s+.0118s------------------------------- = .0116s3.058m/.0116s------------------- = 5m/s.0116Calculating the TE of the small piece of PVC pipe as it passes through the photo gate.PE=mgh=(.0116kg)(9.81N/kg)(.266m)=0.030JKE=1/2mv"=1/2(.0116kg)(5m/s)"=0.145JTE=PE+KE=0.175JCalculating the difference in TE between the top of the tube and the photo gate.212J-.175J=.037J.175J-------- = 83%.212J100%-83%=17%This shows that we incurred a loss of 17% of the TE between the drop of the small piece of PVC pipe and it passing through the photo gate.Conclusions/Sources of ErrorWe found that the experiment was not perfect but the formula does seem to be accurate. Our groups experiment showed a 17% loss in energy between our original total energy calculation at the top of the tube and our total energy calculation as the object passed through the photo gate. This loss in energy can be accounted for by friction between the small piece of PVC pipe and the inner wall of the large pipe, as well as the impact of air molecules on the small piece of PVC pipe.Sources of error for this experiment mostly come in the form of setup; if our large PVC pipe was at a small angle it would have increased friction and decreased the total energy of the small piece of PVC pipe as it passed through the photo gate.