Sunday, February 17, 2008

Snowmobiles Faster Than A Speeding Bullet, Maybe, But Not Light

I'm glad this writer spotted something fishy about the accident report.

Mr. ... and his brother ....were traveling across (the) lake around 10:30 p.m. at an apparent high rate of speed when (they) came upon the shore and hit a maple tree ... 'He was overdriving his headlights. The shore came up too fast and he hit a maple tree

The writer certainly questioned, and rightly so, the phrase "overdriving his headlights", because it implied that the snowmobile was moving faster than the headlights! Awful! :)

Still, this accident report is practicing what I wrote earlier about the propensity of news editors and other "official-type" reports of using the phrase "rate of speed", when all they meant was just "speed". If all they meant was that the vehicle was moving fast, then "rate of speed" is the wrong expression, because this is acceleration. An object could have an instantaneous speed of 0 and yet, still have the highest "rate of speed" it will have in its motion (example: oscillating mass on a spring).

More media writers need to have better physics education. Unfortunately, based on this news report, so do people in a Department of Inland Fisheries and Wildlife



Kent Leung said...

Since I like to give people the benefit of the doubt :), I think by "overdriving the headlights" they mean that their speed x their reaction time (or minimum reaction distance) was greater than the distance of visibility their headlights provided.

Sorry if the author already explains this. I never did read the original article.

phule said...

The phrase "overdriving your headlights" has been taught in driving schools for ages.

It's nothing more than a concise way of stating what the first reply already said: you're driving faster than you can safely react to obstacle being illuminated by your headlights."

This is not the same as the phrase "rate of speed."