I think it would be better if weather forecasts wordlwide used m/s

I don't see how km/h or mph convey anything over and above an arbitrary scale. Units like km/h are really for journey times or comparison with different modes of transport. So why not get used to the proper SI unit?

Phil Hall


----- Original Message ----- From: "Pierre Abbat" <[EMAIL PROTECTED]>
To: "U.S. Metric Association" <[email protected]>
Sent: Wednesday, January 25, 2006 2:16 PM
Subject: [USMA:35845] Re: Speed in km/h vs m/s


On Wednesday 25 January 2006 04:44, John Hynes wrote:
In the US, speeds are usually regulated in increments of 5 mph.  (I have
seen one or two exceptions.)  1 m/s is about 2.237 mph, so here are some
rounded conversions:

MPH   m/s    km/h
 5         2         8
10        4        16
15        7        24
20        9        32
25       11       40
30       13       48
35       16       56
40       18       64
45       20       72
50       22       80
55       25       89
60       27       97
65       29      105
70       31      113
75       34      121

It is not hard to imagine that if road speeds were to be expressed in m/s,
that a smaller number of 5 m/s increments would be used.

m/s   MPH     km/h
 5        11       18
10       22       36
15       34       54
20       45       72
25       56       90
30       67      108
35       78      126

To keep about the same increment as the 5 mph, it might be a good idea to use an increment of 9 km/h, thus making speeds that can be converted exactly to m/s (the unit to use when thinking about a car accident) without any trailing
repeating decimals.

phma



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