At the end of class, he revealed a bike-pedal generator hooked up to a 100 W light bulb, and another one on a more regular lamp.
Guess who volunteered to operate it?
Transcript of what happened with me on the generator bike:
"As you can see, Adam's not having much trouble pedalling the bike."
"There's very little resistance, but that's about to change; he'll have a lot more resistance when I throw the switch. We'll get into why that is near the end of the semester, but let's see how much power he can put out."
"...the resistance did increase, right?"
"Yeah." *shrug* "Not too much."
"All right, I think you better slow down or stop before that light bulb explodes. Class, if you hadn't noticed, the light bulb Adam's powering is brighter than the one on the lamp."
"Anyway, good job!"