I'm going to rephrase the question. Why, is there a difference between a statute mile and nautical mile?

Question

I know they are different lengths and all that stuff about 360 degrees and radians ect. but WHY ( not what ) is there a difference between the two. The earth is the earth, and it applies to both types of miles, so they should be the same length. What makes the lenghts different, they should be the same.

Answer 1

It is very hard to justify why, but the main reason that they came up with the two sets, depends on relativity.

In America, and in a small number of other countries, an odd system of measurement is used. It is based on inches. As you get more inches you get a foot, and with more feet you get a mile. This mile was defined to be of assistance in measuring semi-large distances. Because of America's measurement system, miles are usually used to rate different distances in the United States.

The nautical mile, in contrast, was defined to create simplicity in describing distances in comparison to the circumference of the earth. It makes calculating large distances easier. For a flight to another country around the world, distance can become easier to realize and assume when you divide the earth into multiple, equally sized parts. Instead of going some random number of miles, you now have a certain number of earth sections to cross. Once you know the circumference of the earth in Nautical Miles, you can name distances much quicker and easier. For example, the earth is 21,600 nautical miles and 24,857 miles in circumference. If you had to figure out the approximate distance of a country one quarter of the way around the globe, you would be able to do it much quicker using the nautical mile.

When traveling to another state, your simple standard mile system will do just fine, but when air or sea travel is required, because of the sometimes large distances covered, a nautical system is adopted to make calculations easier. If you had to get half way around the world, planning your trip might be a slim bit easier if you plan it in nautical miles.

I know it may be difficult to understand why both systems were created, but both have their uses and can be equally important in many situations.

Answer 2

Quite a knotty Q: easier at sea to have all of 2000 yards, in round figure, in a mile, which then is a sea mile!makes life simple!

Answer 3

why is there a difference between a metric ton(2200lbs.) and a ton (2000 lbs.)..gravity is still gravity?

Answer 4

It's because water is curved differently than land, silly!
Water has those wavy things and is more squishy.