A lightning bolt hits the CN Tower in Toronto.Aaron Vincent Elkaim/The Canadian Press
This week, Collected Wisdom is up on the roof in a raging thunderstorm to shed light on – Zzzzzt! – a highly charged topic.
THE QUESTION
Ottawa's Gary Pluim wonders why he doesn't seem to see lightning rods on buildings any more.
THE ANSWER
They're still there, but you just can't always see them, according to Yosh Imahori, a fire-protection engineer with the Office of the Fire Marshal in Toronto.
He points out that a lightning rod is merely a conductive metal rod installed on a building to intercept any lightning that might otherwise touch down nearby. "In Ontario," he says, "lightning rods have been installed on buildings as small as a cottage and as large as a skyscraper."
While the Ontario Fire Code and the Ontario Building Code do not require lightning rods to be installed on the top of buildings, he says, there are recognized standards for their installation. For instance, the equipment may be disguised as an alternative structure. Antennas or other transmitting devices may double as lightning rods.
He adds, "while not code-specified, it is considered good practice to provide lightning protection on farm buildings."
THE QUESTION
Victoria's Norman J. Ruff asks: "Which of my face shaves is 'greener' – when I use my rechargeable electric razor or using my razor blade (a Mach 3), shaving cream and hot water?"
THE ANSWER
"The greenest shaving alternative is actually a straight razor," writes Alex Woolcott of Montreal. "A good straight razor should last you for years, as long as you keep it sharp. It's also the only alternative that does not create waste (as disposable razors do) or use up energy (as electric razors do)."
Not so fast, says Trevor Hancock of Victoria. "Norman Ruff's greenest shaving option is to grow a beard. No electricity for a razor, no shaving cream, no hot water – just the occasional trim with a pair of scissors."
THE QUESTION
Mark Eisenman of Toronto wonders why the glasses found in most hotel rooms are so small.
THE ANSWER
"I think there are three reasons," says Michael Greason of Toronto. First, the small glasses "drive you batty in the hope that this will result in guests visiting the hotel restaurant or bar." Second, guests won't think it's worth stealing such useless glasses. Third, if the glasses are actually stolen or broken, they're cheap to replace.
Tom Pater
THE QUESTION
Why, asks Edmonton's Bill Barr, do headlights on some vehicles have three or four small bumps?
THE ANSWER
The bumps are there so that the mechanical devices used by manufacturers and well-equipped garages to aim headlights can be accurately aligned with the surface of the headlights.
James A. Douglas of Ottawa explains: "Aiming means adjusting them so that they point down toward the road and are not shining high enough to disturb oncoming drivers on low beam."
HELP WANTED
- In the media recently, there was news that the expansion of the universe is speeding up, writes Don Campbell of Burlington, Ont. “My question is, into what is the universe expanding?” This, he writes, “brings up the mind-boggling concept of infinity.” He wonders whether anyone has ever put forward a rational explanation of how infinity can be. (Which prompts CW to comment: “Infinity? Don't get us started on infinity.”)
Let's hear from you: If you have the answer to this question (or want to pose a question of your own) send an e-mail to wisdom@globeandmail.com. Please include your name, location and a daytime phone number.