Why does it weigh 16 tons?

Question

Why is it that whenever a huge weight falls on somebody's head, it always weighs 16 tons? Why not a more round number, like 10 or 20?

Answer 1

That was a classic weight established back before the medias of today existed.

But seriously, why ask why?

After all, anything is possible in an animated cartoon or comic.

Otherwise, the character that just got clobbered wouldn't be back a couple of seconds or panels later.

Answer 2

Because of the song, of course.

Answer 3

Huh, I never noticed...maybe it's just some inside pun. Maybe they made it just so that we would wonder like this ;)

Answer 4

maybe it is his unlucky number or its a devilish thing or just a coincidence