In a subtle attempt to gain Alpha-male status, my son left me a physics problem that he could not solve.
He is taking AP Physics as a senior in high school, so it's college freshman level stuff. This problem required that I discover the coefficient of dynamic fiction if a 5 kg block falling straight down could drag a 10 kg block 1 m in 1.2 seconds. The best part, of course, is that the problem had stumped my lad.
Why let a little 25 year hiatus slow me down?
I had to go all the way back to page 13 to get one formula I needed, and I had to review the example problems about 5 times each, but that's not the point. The point is that I not only solved it, I solved it with book rigour. :-) I confessed to him that it took me the better part of an hour, and that I made 2 false starts (for which the errant paperwork was somehow lost) but he still had ample opportunity to call me nasty names.
And THAT is what a father lives for. :-)