Why is SI easier than the English system?

Answer 1

Most measurements are more of habits learned than anything else. So, a yard vs a meter is only what one is used to dealing with.

The metric system has a couple of advantages. It is based on the decimal system, with standardization of units and prefixes. It makes comparisons from one unit to another easier and more logical.

It is "logical" that 1cc = 1ml. 1 liter water (very common) = 1 kg, etc.

The "English" system has different bases from 12 for inches to 5280 feet per mile. Cups, pints, quarts, teaspoons, tablespoons, etc are all somewhat obscure measurements. There are even different sizes of gallons depending on what substance one is discussing, or which country a person is in.

However, not all is bad with the "English" system either. Fractions can be logical. Halves, Quarters, Eighths, Sixteenths, etc. often just make sense.

And, while Fahrenheit isn't based on freezing and boiling of water, it is based more or less on a "normal" temperature range that people are likely to experience. I.E. in much of the world, 0°F is very cold, and 100°F is very hot. Anything falling outside of that range would be considered extremes.

But, then again, perhaps that is just a habit, and it would be equally logical to think of -10°C being chilly and 40°C being hot.

The reason why many who use the metric system prefer it, was summed up by one contributor in this way:

"The metric system is based on tens, hundreds and thousands - simplicity itself. The Imperial system uses threes (feet in a yard), eights (pints in a gallon, also furlongs in a mile), twelves (inches in a foot), fourteens (pounds in a stone), sixteens (ounces in a pound and also fluid ounces in an American pint), twenties (fluid ounces in a British pint) - need I say more???"

Answer 2

International System of Units (SI) are widely used. SI is based on seven quantities. Length - meter, mass - kilogram, time - second, electric current - ampere, themodynamic temperatuer - kelvin, amount of substance - mole and luminous intensity - candela.

Answer 3

The SI is much, much easier than "US Customary" units (the English don't want to be held responsible for what Americans use), for several reasons:

• There is only one unit for each type of measurement in the SI. Let's take three examples:
  • For distance, in the SI there are meters and that's it; everything else is just a power of ten. On the other hand, the US Customary system has mils, inches, feet, yards, rods, furlongs, miles, nautical miles and leagues, with strange conversion factors between them all.
  • For volume, in the SI, there are liters and that's it; everything else is just a power of ten. On the other hand, the US Customary system has drams, teaspoons, tablespoons, ounces, gills, cups, pints, quarts, gallons, pecks, bushels, drums, beer barrels, liquid barrels, whiskey/kerosene barrels, oil barrels, cubic inches, cubic feet, cubic yards and I don't know of anyone who can remember the conversion factors for all those units! Oh--don't forget--a dry pint, quart, gallon or barrel is not the same thing as a fluid pint, quart, gallon or barrel, respectively.
  • For mass, in the SI, there are grams and that's it; everything else is just a power of ten. On the other hand, the US Customary system has... well, first of all, it doesn't even have units for mass, but it has weight, which works some of the time. Units of weight: ounces (which, of course, are not the same thing at all as the "ounces" used for volume--just for extra confusion), pounds, hundredweight and tons.

• In the SI, when values get very large or very small, you don't have to convert to another unit, you just use a prefix to switch to another power of ten. No arithmetic needed, no calculator required, no conversion factors to remember; just move the decimal point.
• The SI does not use fractions like quarters, eighths, and sixteenths! Everything is decimal.
• The SI has easy to remember relationships. A liter of water is one kilogram, so one milliliter of water is one gram. Water freezes at 0oC and boils at 100oC. (OK, the Celsius degree is not an SI unit, but it is metric and it is directly related to an SI unit, the Kelvin). This gets even more important when you have to do calculations with units for force, power and energy.
• There are no US Customary units for anything involving electricity.
• Finally, the US Customary system just breaks down completely when dealing with very small quantities. Modern technology deals with very tiny things, which are measured in nanometers. There are no US Customary units which are practical for those measurements.