There’s nothing in either the metric system or the English system that sets limits on things.
Take the bolts and nuts issue brought up above. In the English system, the pitch is specified in “threads per inch”. There are standards, but that doesn’t preclude anyone from making something off standard. In fact, there are places where an adjustment screw has used an ultra fine thread that isn’t part of the standard (as in UNC and UNF).
The same for metric - but in this case they specify the pitch as the distance between threads. There are standard thread pitches, but there is nothing that prevents someone from using an unusual pitch.
A million microphones is not a phone. It’s a million microphones.
A microphone is not a millionth of a phone. It’s a device to convert sound waves into electrical impulses, generally piezoelectric or inductive.
A megaphone is not a million million phones. Or a trillion microphones, or a peta-microphone. It’s a device for amplifying speech.
Naw, my soul is safe and happy. As is my admittedly unique sense of humor.
But people get easily confused with metrics. Good Lord, would this thread cause them consternation!
The metric system is still greatly distrusted. Not sure what their present attitude is, but the American Rodeo Cowboys Association told the world it was a Communist plot to overthrow the USA. Never mind it was Napoleon who introduced it in the early 1800s, and the Russian Revolution who, with most of the developed world, adopted it.
On the other hand, calling a quarter horse a “396 meter horse” needs some selling.
Honestly, as long as everybody understands whatever the unit of measuer is, what difference does it make?
But I still can’t figure out how the tire industry settled on a mix of the two.
“But people get easily confused with metrics.” Of course that only happens if they were taught the silly English system based on length of the King’s arm.
I was confused with the metric system when I entered high-school. I was taught nothing but SAE prior. But I learned quickly how much easier working with metric measurements is then SAE. Everything in Metric is a factor of 10. When you start doing physics problems it becomes abundantly clear how much easier doing calculations in Metric is so much easier.
The meter was based on one minute of arc on the surface of the earth…as best it could be determined in 1670. So basically it was based on something logical but not at the time accurately determinable.
The meter was based on one minute of arc on the surface of the earth......as best it could be determined in 1670.
There was a philosopher back in the 1600’s that was able to determine circumference of the earth by having two people 100 miles apart hold up a stick at exactly noon and then measure the length of the shadow. The difference in lengths of the shadows and he was able to determine the circumference of the earth with amazing accuracy. Saw it on Nova a few years ago. Amazing what people (geniuses NOT me) come with so little resources when they have to.
My favorite is the reason the US gallon is different than the ‘Imperial’ gallon - one’s based on the size of a wine barrel, the other’s based on the size of a beer barrel, way back when. Those are units I can enjoy!
MikeInNH — "The meter was based on one minute of arc on the surface of the earth."
Less one think that all non-metric units are frivolously based, the nautical mile is a unit of length approximately equal to one minute of arc of latitude along any meridian, or one minute of arc of longitude at the equator. By international agreement it is exactly 1,852 meters or approximately 6,076 feet.
And the knot is a unit of speed (a good Anglo-Saxon word vis-à-vis “velocity”) equal to one nautical mile per hour.
Until the mid-19th century vessel speed at sea was measured using a chip log, consisting of a wooden panel, weighted on one edge to float upright, and thus presenting substantial resistance to moving with respect to the water around it. The chip log was attached to a knotted line, cast over the stern of a moving vessel, and allowed to pay out. Knots placed at a distance of 47 feet 3 inches passed through a sailor’s fingers, while another sailor used a 30 second sand-glass to time the operation. The knot count would be reported and used in the sailing master’s dead reckoning and navigation. This method gives a value for the knot of 20.25 inches/sec, or 1.85166 km/h. The difference from the modern definition is less than 0.02%.
Thus the nautical mile is a scientific unit of measurement (equal to one minute of latitude anywhere or one minute of equatorial longitude) and the knot is an historical and scientific unit of measurement dating back to Lord Nelson and Trafalgar. Not some moldy unit born in an 18th century lab in overcast Bamburg.
“Thus the nautical mile is a scientific unit of measurement (equal to one minute of latitude anywhere or one minute of equatorial longitude)”
Of course the minute is based on ???
Frankly I can’t understand why someone would chose to have water freeze at 32º and boil at 212º while most of the rest of the world has water freeze at zero and boil at 100º
Mountain Bike said: “But I still can’t figure out how the tire industry settled on a mix of the two.”
I know the answer to that.
Way back when, pretty much everything was in inches. When they changed over to metric, there was this residual problem of the wheels (rims) Since the wheels were sized in inches - as it’s really a designation, not a dimension - there was not only a good reason to leave the designation alone, but changing would have created an instant problem of what tires would go on older cars. Better to live with a mixed system.