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125 Years of Longitude 0 0' 00" At Greenwich
An anonymous reader writes "This week marks the 125th anniversary of the International Meridian Conference, which determined that the prime meridian (i.e., longitude 0 0' 00") would travel through Greenwich, UK. One of the reasons that Greenwich was agreed upon 'was that 72% of the world's shipping already depended on sea charts that used Greenwich as the Prime Meridian.' Sandford Fleming's proposal of a single 24-hour clock for the entire world, located at the center of the Earth and not linked to any surface meridian, was rejected / not voted on, as it was felt to be outside the purview of the conference."
And don't forget the 180th meridian that came with it. When you cross the 180th meridian, you have to set your watch back/forward 23 hours !
Quite a few people are unaware of it ;-))
http://adsabs.harvard.edu/full/1919PA.....27..416F
Everything I write is lies, read between the lines.
It's a wonderful thing to live a phlegms breath away from such a staple part of our species everyday lives.
I wonder how much longer it will take for the US to catch up?
For example, we continue to teach date formatted in a completely nonsense format (MM/DD/YYYY) instead of either high to low (YYYY/MM/DD) or low to high (DD/MM/YYYY) like the rest of the world. Plus using AM/PM instead of 24 hour ("Military Time") again like the rest of the civilised world.
Don't even get me started on our lack of metric....
Your link says nothing at all about WGS84. Here is one that does: http://en.wikipedia.org/wiki/World_Geodetic_System
It's called Riyadh Solar Time - look it up. It last one year year before they realised how much of a pain in the arse it was. Also, Japan used to have per-city time zones in five-minute increments, and that was a real pain for doing business, or calculating journey travel/arrival times. Discrete time zones for relatively large areas are just more practical in general.
Clearly you're not a woodworker. Small measurements are where the metric system shines... large measurements people just estimate anyway.
"Growing old is inevitable; growing up is optional."
stores [open] 3 hours before local midday
You imply that the entire population can consistently and correctly subtract 3 from a number.
- Video. The PAL standard is better quality than NTSC (Never The Same Color), so why did the Americas adopt an inferior option?
That's sort of like asking why we adopted the clearly inferior analog STDV standard instead of digital HDTV. NTSC was standardized in 1953, PAL was not standardized until 1963. Naturally, PAL was the superior standard...it was based around technology that was ten years more advanced.
You miss the point. The advantage of using the same base across all measurements is not merely that it goes well with the digits we use, but it means different type of measurements work well together. A cubic meter works out to exactly a thousand liters, which when filled with water would weigh 1 metric tonne, which is 1 thousand kilograms. The pressure of 10 metres of water works out to 1 atmosphere, which is approximately 100,000 Pascal, which is 100,000 Newtons per square meter. At sea level the acceleration due to gravity is approximately 10 M/s so 1kg is roughly 10 newtons worth of weight. If you have a force of 1 Newton over 1 meter , you get 1 joule worth of energy, which is the energy drawn per second by 1 ampere of electric current at an electric potential of 1 volt.
Now, lets say you have a pool of water that is 10 feet deep and 10x20 yards by the sides. You want an electric engine operating at 230V to drive a pump that can empty the pool through a pipe that has a diameter of 3inches. The drain is at ground level. You don't want to leave it on unsupervised at night so you want it to take no more than 2 hours. How many amperes of current will your engine draw? What's the total amount of energy necessary to empty the pool? How much pressure does the pump have to handle?
I would STRONGLY suggest you convert to SI units before trying to solve that problem.