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Romeo
Senior Post God Joined: 16 November 2008 Location: Canada Status: Offline Points: 3033 |
Post Options Quote Reply Posted: 23 September 2011 at 7:32pm | |
I don't know. I find both ibs-ft and Nm totally equal, as far as calculations go. In fact, I'll one-up that statement. I find ibs-ft and HP easier to calculate than Nm and KW. We all know the old Pounds-foot X RPM / 5252 = Horsepower. Not too many people know what calculation takes Newton-Metres over to KiloWatts, myself included.
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Never shift into reverse without a back-up plan.
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Colby
Admin Group Joined: 30 March 2009 Location: Abbotsford/Sask Status: Offline Points: 665 |
Post Options Quote Reply Posted: 23 September 2011 at 8:05pm | |
Believe it or not, you've just proved my point. Where do you think 1/5252 comes from?
In metric: P=T*w where T is torque in Nm, w is frequency in radians per second and P is power in watts. 1/5252 is to the ratio to convert it so the variables can be in imperial. Imagine needing to remember an extra constant for each calculation, that's no fun. |
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88 Formula 5 speed
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karnak
Senior Member Joined: 28 August 2009 Location: Canada Status: Offline Points: 349 |
Post Options Quote Reply Posted: 23 September 2011 at 10:51pm | |
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Romeo
Senior Post God Joined: 16 November 2008 Location: Canada Status: Offline Points: 3033 |
Post Options Quote Reply Posted: 24 September 2011 at 1:04am | |
...No it's not. The 1/5252 is simply an abbreviation of the angular speed. Yes, it does take in to account the torque's distance (The "foot" part of "pounds-foot") but that's always a static measurement. Something else to consider is that Imperial and Metric are just as complex - one couldn't be more complex for the other for the calculation to make sense. Ibs-ft = How many pounds of force are being applied in a foot of work. Nm = How many Newtons of force are being applied in a metre of work.
It should also be noted, that technically speaking, when dealing with metric, you don't have the nice easy "Torque X RPM / 5252" formula. If you follow metric to the most stringent of definitions, you'll find they calculate in radians per second. Good luck getting that off your tach. |
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Never shift into reverse without a back-up plan.
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AllanJ
Senior Member Joined: 28 July 2010 Status: Offline Points: 254 |
Post Options Quote Reply Posted: 24 September 2011 at 9:46am | |
My poor thread....
Sorry to be (now) OT... The Race Keeper folks updated their gauges so now the accelerometer has 1g and 2g markings on it to give you a little better idea of the lateral and longitudinal g-forces. Have a look if you're curious. Video link |
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Colby
Admin Group Joined: 30 March 2009 Location: Abbotsford/Sask Status: Offline Points: 665 |
Post Options Quote Reply Posted: 24 September 2011 at 10:46am | |
Yes it is, I even worked it out to verify. I got 0.000189 putting in some rough conversion factors and putting them all on one side. Compare that to 1/5252 = 0.0001904. You can call it "an abbreviation of the angular speed" if you want, but it's there because of the issues with imperial. Metric was designed to make calculations simpler. Units are defined in terms of other units, rather than on an arbitrary measurement, ie. watts = newtons x meters compared to horse power which is some arbitrary unit so people could roughly compare the power output to that of a horse. Because of this, yes, sometimes it's awkward to measure with, but that's no reason to hate it. |
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88 Formula 5 speed
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Patrick
Newbie Joined: 19 April 2008 Location: Vancouver Status: Offline Points: 5 |
Post Options Quote Reply Posted: 24 September 2011 at 2:04pm | |
Colby... Tristan... get a room!
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