Joke check

[nancylebov]

I'll probably get bumper stickers printed in red that say "If this is blue, you're driving too fast."

It's occurred to me that I could add another twist to the joke by having them printed in blue, but I'm not sure whether that version of the joke would be either comprehensible or funny. What do you think?

If you and a source of waves are moving toward each other, the waves seem closer together. Blue light has shorter waves than red, so if something red looks blue, you're closing on that bumper much too fast.

Comments

[redaxe.livejournal.com]

I like the original (printed in red). It's understandable to anyone who knows some high school physics, and easily explainable to anyone capable of understanding such (as you yourself do above).

The second twist would be funny in the hypothetical situation where the first joke became popular, as a followup.