More on metric

I'm writing this as a response to a great comment on my post about metric system use in the US.

Do you really think so? Speedometers have both metric and imperial units, but I don't think that's done much to improve "metric literacy" in the 'States.

Listing metric measurements after the imperial units doesn't quite say "these units are the ones we will be using." Even then, the things that list both don't really have "teeth." Switching speed limit signs to metric only would, I think, have a much larger effect since people could be punished for failing to process the information.

But, yes. Hooray for New Hampshire!

True enough anonymous. That being said, speedometers are easier to ignore. It's an analog measurement so you don't get the effect of repeated drilling of a=b. Also, the metric numbers are way smaller and on the inside loop. It's true that you could just look at the left side of the sign, but I think the minimum benefit would be a definition for a number of common mileages (1, 1/2 etc). I'd guess a fair number of people know that 100 k/h is close to 60 mph because those actually have lines on the speedometer and they're pretty close. Likewise I'd bet lots of people know 0°C is the same as 32°F because that's a temperature that people are exposed to (on both scales) on a regular basis. I'd bet 32 f/s being equal to 9.8 m/s is also not uncommon.

Here's a long-term plan I just came up with right nowish. Whenever an all-imperial sign needs to be replaced, put up a sign with imperial units followed by metric units in parentheses. When on of these imperial-metric signs needs to be replaced, put up a metric-imperial sign that has metric units followed by imperial units in parentheses. At some pint, once everyone is pretty hip on things, stop having imperial units on the signs at all. Hooray!

I don't think teeth are needed. I don't think this is a switch we can, should or will make quickly. My thought is pretty much that the next generation should be heavily exposed to metric - they should become SI literate even if we have failed to do so ourselves.

Is this just me? If I think about how many meters are in 32 feet, I take quite a while to get a correct answer. First I estimate by using yards and I get just under 11 meters. On my second pass, I use 1 m = 3.3 ft and get that it's just under 10 m. Win.
It's odd that my mind doesn't just think of the fact that it knows 9.8 m/s ~ 32 f/s and that it can just cancel the seconds and get to a much faster, more correct answer...