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> That's mostly true because it seems yards are only used to measure football fields and fabric. Also shooting ranges, but yes. > There's a highway exit comin

> That's mostly true because it seems yards are only used to measure football fields and fabric. Also shooting ranges, but yes. > There's a highway exit coming up in 800 feet and another in 1/2 mile. How many times longer does it take to reach the second exit compared to the first exit? Prior to GPS navigation nobody ever said "there's a highway exit coming up in 800 feet"; road signs in the US consistently use fractions of a mile. When my GPS app switches units from fractions of a mile to feet, that means I can see where I need to exit/turn. Calculating a precise ratio doesn't matter. It's between 6 and 7 since there's 5280 feet in a mile and 86 is 48 but 87 is 56, but who cares? Also, on a highway, I'm usually traveling at least 60 mph, and since there's 60 minutes in an hour, that comes out to one mile per minute. Try that with your fancy metric system! > Tell me you haven't worked in engineering without telling me you haven't worked in engineering. If you eyeball everything and use intuition, I can see why you don't care about units, conversions, and calculations. You're imagining a scenario where a guy who's worrying about fractions of an inch building a cabinet has to talk to the city planner who's worried about miles and they have to convert units to do that. That doesn't happen, and yet you want to optimize the entire unit of measurement for that specific use case at the expense of more common use cases like "dividing by three". When it comes to domains where consistency does matter, we just don't do unit conversions. For instance, flight altitude is measured in feet, even when it's thousands of feet, instead of miles. If you're flying an airplane at 30,000 feet, who cares how many miles that is? That's not what miles are for. Likewise with domains that use feet per second rather than miles per hour. Again, even "metric" countries don't commit to the bit here; name me a country where the highway speed limit is in meters per second.

nayuki 3y ago
> When it comes to domains where consistency does matter, we just don't do unit conversions. For instance, flight altitude is measured in feet, even when it's thousands of feet, instead of miles. If you're flying an airplane at 30,000 feet, who cares how many miles that is? Wrong. https://en.wikipedia.org/wiki/Gliding_flight#Glide_ratio https://en.wikipedia.org/wiki/Gliding_flight#Glide_ratio Your plane is up at 30000 feet and your engines are out. The nearest airport is 47 nautical miles out. The plane has a glide ratio of 15. Will you make it? It's easy in metric: 9.1 km altitude, 87 km distance. > Again, even "metric" countries don't commit to the bit here; name me a country where the highway speed limit is in meters per second. I actually much prefer metres per second. It makes things like kinetic energy calculations easier. If I wanted to know the KE of a 1500 kg, 100 km/h car, I would first need to convert to m/s. Ditto the kilowatt-hour; it needs to die in favor of megajoules.
- philwelch 3y ago
  > Your plane is up at 30000 feet and your engines are out. The nearest airport is 47 nautical miles out. The plane has a glide ratio of 15. Will you make it? Nautical miles and statute miles are different units anyway, so my initial assertion--that you would never convert flight altitude to statute miles--is still correct. Glide ratio varies according to speed; the plane might have a glide ratio of 15 at one speed but a different glide ratio at a different speed. So in practice, the real world version of this word problem is more complex than you make it out to be, and pilots' handbooks will commonly have tables of glide distances to consult for this reason. > If I wanted to know the KE of a 1500 kg, 100 km/h car, I would first need to convert to m/s. You've adequately demonstrated that metric is more convenient for arbitrary word problems that you've provided. Real world applications is what I'm less convinced about.
tstenner 3y ago
> Also, on a highway, I'm usually traveling at least 60 mph, and since there's 60 minutes in an hour, that comes out to one mile per minute. Try that with your fancy metric system! All right. I'm travelling along the highway at 120 kilometers per hour, which is 2 km per minute. Where ist the problem?

nayuki 3y ago

> When it comes to domains where consistency does matter, we just don't do unit conversions. For instance, flight altitude is measured in feet, even when it's thousands of feet, instead of miles. If you're flying an airplane at 30,000 feet, who cares how many miles that is? Wrong. https://en.wikipedia.org/wiki/Gliding_flight#Glide_ratio https://en.wikipedia.org/wiki/Gliding_flight#Glide_ratio Your plane is up at 30000 feet and your engines are out. The nearest airport is 47 nautical miles out. The plane has a glide ratio of 15. Will you make it? It's easy in metric: 9.1 km altitude, 87 km distance. > Again, even "metric" countries don't commit to the bit here; name me a country where the highway speed limit is in meters per second. I actually much prefer metres per second. It makes things like kinetic energy calculations easier. If I wanted to know the KE of a 1500 kg, 100 km/h car, I would first need to convert to m/s. Ditto the kilowatt-hour; it needs to die in favor of megajoules.

philwelch 3y ago
> Your plane is up at 30000 feet and your engines are out. The nearest airport is 47 nautical miles out. The plane has a glide ratio of 15. Will you make it? Nautical miles and statute miles are different units anyway, so my initial assertion--that you would never convert flight altitude to statute miles--is still correct. Glide ratio varies according to speed; the plane might have a glide ratio of 15 at one speed but a different glide ratio at a different speed. So in practice, the real world version of this word problem is more complex than you make it out to be, and pilots' handbooks will commonly have tables of glide distances to consult for this reason. > If I wanted to know the KE of a 1500 kg, 100 km/h car, I would first need to convert to m/s. You've adequately demonstrated that metric is more convenient for arbitrary word problems that you've provided. Real world applications is what I'm less convinced about.

tstenner 3y ago

> Also, on a highway, I'm usually traveling at least 60 mph, and since there's 60 minutes in an hour, that comes out to one mile per minute. Try that with your fancy metric system! All right. I'm travelling along the highway at 120 kilometers per hour, which is 2 km per minute. Where ist the problem?