This is a detailed explanation of the experimental results in comparison with theory. Did the results agree with theory or prediction? Is some unknown factor operating? Try to look very carefully at the experiment and analyze it in detail. Do not simply recap the RESULTS section.***
***In this section you should also look for errors in the experiment. It is very tempting to blame one's lab partner or even oneself for what seem to be experimental errors. However there are other possibilities that are just as likely. Some experiments are not well designed. They permit other factors to influence the results. Some equipment is inadequate or defective. If you are observant, you can figure out why your results are inconsistent or unexpected.