Three Wise Guys: Leaf-Blower Neighbor, Falling Into the Earth, Fitted Sheets Again

(By Danny Hellman)
  Enlarge Photo    
By Joe Heim, Justin Rude and Dan Zak
Sunday, June 1, 2008

Dear Wise Guys:

What do you think the punishment should be for a neighbor who takes his leaf blower up on his roof and spends a solid hour blowing every molecule of dirt off a tiny (maybe 20-by-30-foot) area while people over a block away are deafened by the noise? He gets extra credit because a neighbor who saw him decided to follow suit.


Justin: If you fight fire with fire, it stands to reason you should fight air with air. With a résumé that includes years of professional groundskeeping, I feel comfortable recommending the fine orange machines made by Stihl. Don't go for the compact and portable hand blowers. They aren't going to impress your neighbor nearly as much as the far more robust backpack models.

Personally, I would go for the BR 600, the Cadillac of leaf blowers, which cranks out wind at an incredible 226 mph with an earsplitting 75-decibel roar. You would be the roof-blower queen of the neighborhood. That thing is so strong that a careless teenage employee could use it to dent a company car with small rocks. Not that I would know anything about that.

Joe: What Justin is recommending is going to lead to a leaf-blower arms race that will leave the neighborhood sounding like a NASCAR event every Saturday morning. Remember, just because this guy blows more than anyone else on the block doesn't make him a villain. Why don't you just ask him (politely) to blow less? If that doesn't work, you and your neighbors should try picketing in front of his house while wearing giant protective ear gear and carrying signs with such slogans as, "Dude, your roof really isn't that dirty."

Dear Wise Guys:

If you could put a pipe through the Earth (let's say North Pole to South Pole) and be insulated from the heat in the middle, and you jumped into the pipe, would you fall out the other side or float in the middle?


Dan: We thought about calling the folks at the North American Jules Verne Society but figured their answer would go something like, "You'd be spewed from a steamy volcano on the Italian island of Stromboli!" Which is incorrect.

Also incorrect: your guesses. Falling out the other side and floating in the middle are two of the most frequent wrong answers given by students in physics professor Jerry Feldman's introductory class at George Washington University, where this very scenario is posed to illustrate oscillatory motion. The correct answer, according to Feldman: You'd "bounce" back and forth between the poles, zooming "downward" toward the center and then slowing "upward" till you reached the other side, then falling back "down."

P.S. How long would a round trip take you? Ninety minutes. What's the Earth's diameter between the poles? About 7,900 miles. We'd try to calculate average speed, but factoring acceleration into the old rt = d formula is a collegiate skill that hasn't stuck with us.

CONTINUED     1        >

© 2008 The Washington Post Company