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 | | From: | Jean Lemire | | Subject: | Knots conversion | | Date: | 3 Jan 2005 10:01:32 -0800 |
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 | Hi folks.
Sorry to start a new thread but Google do not allow me to post a reply
to some of the posts in the thread about "wind speed".
According to the Mark's Standard Handbook for Mechanical Engineers,
eighth edition, the International Nautical Mile is given as 6076.11549
feet. A knot is one nautical mile per hour.
Since the mile used on land is 5280 feet, the division of 6076.11549
by 5280 yields 1,1507794488636363636363636363636 which can be
approximated to 1.15.
So 1 knot would be around 1.15 mi/h (or mph or mile per hour).
Also, knowing that 1 foot is 0.3048 meter, allows you to calculate
that one nautical mile is approximatively 1852 meters or 1.852 km.
Hence, 1 knot is about 1.8 km/h.
An easy to do conversion from knots to km/h is to take the speed in
knots and multiply by two then subtract 1/10 of the value (that's
equal to multiplying by 2 then subtracting 0.2 which is equal to
multiply by 1.8 (2 - 0.2 = 1.8).
Lets use a practical example: the wind is given as 20 knots.
20 times 2 equals 40
1 tenth of 40 equals 4
40 minus 4 equals 36.
Of course 20 times 1.8 equals 36. A more precise value would be 37.04
using the 1.852 result given above.
Just ideas.
Jean (Johnny) Lemire from Richelieu, Quebec, Canada.
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| | From: | tom A | | Subject: | Re: Knots conversion | | Date: | Tue, 04 Jan 2005 04:20:23 GMT |
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| HI Johnny
I haven't thought about it for a while, but with all the
meters/kilometers ect.
I have often wondered why in Canada all the speed limits are posted
in kilometers, but when ever you see a sign saying "Joe's Gas
Station 2 miles ahead"
is that because some guy name "JOE" moved to Canada from the US and
opened a gas station ??
tom A.
On 3 Jan 2005 10:01:32 -0800, j.lemire@tecsult.com (Jean Lemire)
wrote:
>Hi folks.
>
>Sorry to start a new thread but Google do not allow me to post a reply
>to some of the posts in the thread about "wind speed".
>
>According to the Mark's Standard Handbook for Mechanical Engineers,
>eighth edition, the International Nautical Mile is given as 6076.11549
>feet. A knot is one nautical mile per hour.
>
>Since the mile used on land is 5280 feet, the division of 6076.11549
>by 5280 yields 1,1507794488636363636363636363636 which can be
>approximated to 1.15.
>
>So 1 knot would be around 1.15 mi/h (or mph or mile per hour).
>
>Also, knowing that 1 foot is 0.3048 meter, allows you to calculate
>that one nautical mile is approximatively 1852 meters or 1.852 km.
>Hence, 1 knot is about 1.8 km/h.
>
>An easy to do conversion from knots to km/h is to take the speed in
>knots and multiply by two then subtract 1/10 of the value (that's
>equal to multiplying by 2 then subtracting 0.2 which is equal to
>multiply by 1.8 (2 - 0.2 = 1.8).
>
>Lets use a practical example: the wind is given as 20 knots.
>
>20 times 2 equals 40
>
>1 tenth of 40 equals 4
>
>40 minus 4 equals 36.
>
>Of course 20 times 1.8 equals 36. A more precise value would be 37.04
>using the 1.852 result given above.
>
>Just ideas.
>
>Jean (Johnny) Lemire from Richelieu, Quebec, Canada.
tom A.
Please check my WeB SiTe: www.kinetickites.com
or call me @ 405-722-KITE (5483)
or E-mail @ kiteman@kinetickites.com
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| | From: | Kiteman - Canada | | Subject: | Re: Knots conversion | | Date: | Thu, 06 Jan 2005 15:42:42 GMT |
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"tom A" wrote in message
news:216kt0hnt6og7gnfp8ei1p2r2mh7i3e8df@4ax.com...
> HI Johnny
>
> I haven't thought about it for a while, but with all the
> meters/kilometers ect.
>
> I have often wondered why in Canada all the speed limits are posted
> in kilometers, but when ever you see a sign saying "Joe's Gas
> Station 2 miles ahead"
>
> is that because some guy name "JOE" moved to Canada from the US and
> opened a gas station ??
>
>
> tom A.
Those would be old signs that people have not bothered to update. It is
actually technically illegal to post or verbalize the old imperial units.
The "miles" system won't be dropped anytime soon, especially in rural
farming areas. These areas were divided up into 1 mile grids (called a
section - 640 acres) a century (or so) ago - it is much easier to tell
someone to "go 2 miles up and turn left" - they know to look for the second
road - rather than saying "go 3.2 km -approx. - and turn left".
Having a big neighbour (U.S.A.) that refuses to switch to metric does not
help matters either.
Tom
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| | From: | Willondon | | Subject: | Re: Knots conversion | | Date: | Fri, 07 Jan 2005 10:00:41 -0500 |
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| Kiteman - Canada wrote:
> "tom A" wrote in message
> news:216kt0hnt6og7gnfp8ei1p2r2mh7i3e8df@4ax.com...
> > HI Johnny
> >
> > I haven't thought about it for a while, but with all the
> > meters/kilometers ect.
> >
> > I have often wondered why in Canada all the speed limits are posted
> > in kilometers, but when ever you see a sign saying "Joe's Gas
> > Station 2 miles ahead"
> >
> > is that because some guy name "JOE" moved to Canada from the US and
> > opened a gas station ??
> >
> >
> > tom A.
>
> Those would be old signs that people have not bothered to update. It is
> actually technically illegal to post or verbalize the old imperial units.
> [...]
I don't think so. I believe the rules govern actual transactions in
certain industries. For example, groceries must be labelled with metric
units (although other units are allowed along side). Houses still
advertise square feet, and furniture is routinely described with imperial
units. There's nothing wrong with advertising that "three miles down the
road you can get a free half-gallon slushie with every fill-up", as long
as the gas is sold in litres, and the slushie has a metric version of
whatever measurements are printed on it.
FWIW, kites and lines are sold here in feet and inches.
--
Willondon
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