Many users are interested in the CO2 emissions (at any rate in the UK where they are used to determine road tax). Fuel consumption of one litre per 100 km generates CO2 at the rate of 22.8 g/km. (Assuming petrol is pure octane and that it has a density of 740 kg/m^3).
From: Charles Peyto [mailto:[email protected]] Sent: 16 December 2013 12:45 To: Martin Vlietstra Cc: U.S. Metric Association Subject: Re: [USMA:53441] RE: 0 to 100 km/h Performance Measure for Automotive Acceleration The car manufacturers generally quote both the 0-60 mph AND the 0-100 km/h (0-62 mph) figures. It is the car buyers and motoring journalists being familiar with their customer base, who tend to be interested in only the mph data. It is the same with fuel consumption data. The manufacturers give both mpg and L/100 km data, but only a minority of consumers are interested in anything but the mpg figures. -- C. On 16 December 2013 12:17, Martin Vlietstra <[email protected]> wrote: Maybe it is the motor manufacturers who prefer imperial figures. It takes at least 6.7% longer for a car to reach 62 mph than it does for it to reach 60 mph, so using 60 mph rather than 62 mph could be construed as a way of deceiving the customer, especially if the acceleration was calculated as an adjunct to fuel consumption figures using the official EU standards (see http://www.dft.gov.uk/vca/fcb/the-fuel-consumption-testing-scheme.asp). The figure of 6.7% was arrived at by noting that the kinetic energy of the car is proportional to V^2 and by assuming that the engine is delivering constant power (ie the rate of energy generation is constant) and that friction, air resistance etc are sufficiently small that the additional drag they produce can be neglected. From: [email protected] [mailto:[email protected]] On Behalf Of Charles Peyto Sent: 16 December 2013 10:32 To: U.S. Metric Association Cc: U.S. Metric Association Subject: [USMA:53441] RE: 0 to 100 km/h Performance Measure for Automotive Acceleration There is NO such law in the UK. 0-60 mph is the common measure of car performance, Wikipedia is correct. The only time units are regulated in the UK is for certain activities involving the sale of items per unit of measure (usually metric has to be used, but for some things imperial is still mandated) and for some public administration activities such as the wording of legislation. In general, the use of units are not regulated in the UK. The population are free to use whichever units they like. The general preference is imperial units for most things, as reflected by the BBC in their output. -- C. -- C. On 12 December 2013 20:36, <[email protected]> wrote: Actually, in the UK it is the law to quote acceleration times as 0 to 62 mph (= 100 km/h), so it is ONLY the USA that uses 0 to 60 mph. John F-L -----Original Message----- From: Ressel, Howard (DOT) Sent: Thursday, December 12, 2013 8:25 PM To: U.S. Metric Association Subject: [USMA:53430] RE: 0 to 100 km/h Performance Measure for Automotive Acceleration I agree, we Americans tend to be a bit arrogant and thing that the only way is the US way. -----Original Message----- From: [email protected] [mailto:[email protected]] On Behalf Of [email protected] Sent: Thursday, December 12, 2013 3:19 PM To: U.S. Metric Association Subject: [USMA:53429] 0 to 100 km/h Performance Measure for Automotive Acceleration My co-worker recently recounted to me her discussion with a car salesman who claimed that 0 to 60 mph is the ONLY performance measure for automotive acceleration used worldwide. He told her this during a discussion in which she was telling him about her co-worker (that's me) who advocates United States metrication. The salesman was arguing that the US should keep its worthy standards because of their worldwide use. I did a little poking around on Wikipedia and discovered that the time it takes to accelerate from 0 to 60 mph is a commonly used performance measure for automotive acceleration in the United States and the United Kingdom. In the rest of the world 0 to 100 km/h is used. http://en.wikipedia.org/wiki/0_to_60_mph so the car salesman was just making it up. I think many Americans tend to make things up or just assume things based on their limited experience. Educate yourselves and be prepared to educate your fellow Americans so we can complete American metrication one person at a time. David Pearl MetricPioneer.com 503-428-4917 ----- No virus found in this message. Checked by AVG - www.avg.com Version: 2014.0.4259 / Virus Database: 3658/6914 - Release Date: 12/12/13
