One of the unfortunate things about being a physicist is that I cannot, generally, take part in the academic passtime of highlighting particularly amusing errors made by my students to delight my readers. This is because the assignments I mark tend to have very little written component, and badly-done calculations just tend to be frustrating.
However, today I had a student write in his lab report that:
“The total energy curve has a slight slope to it because the value of time changes due to friction.”
I’m pretty sure time keeps changing no matter how much friction there is.
EDIT: Mind you, in a round-about sort of way, the student is actually right that because of friction, energy is lost in the form of heat, thereby increasing the entropy of the universe and ensuring that time only points forwards, but somehow, I don’t think that that is what he was thinking about.