The US Customary System is a set of weights and measures predominantly used in the United States. While the majority of the world has adopted the metric system, the US Customary System remains widely in use within the United States, especially for everyday and non-scientific purposes.
Detailed Definition
The US Customary System, derived from the British Imperial System, comprises various units of measure for length, area, volume, mass, and temperature. Some of the most common units include inches, feet, yards, miles, teaspoons, tablespoons, cups, pints, quarts, gallons, ounces, pounds, and degrees Fahrenheit.
Length
- Inch (in): The basic unit of length in the US Customary System, with 12 inches constituting a foot.
- Foot (ft): Equals 12 inches or 0.3048 meters.
- Yard (yd): Equals 3 feet or 0.9144 meters.
- Mile (mi): Equals 5,280 feet or approximately 1.60934 kilometers.
Area
- Square Inch (sq in): Area of a square with sides of one inch.
- Square Foot (sq ft): Area of a square with sides of one foot (144 sq in).
- Acre: Equals 43,560 sq ft or approximately 4,046.86 square meters.
Volume
- Teaspoon (tsp): Equals 1/3 tablespoon or approximately 4.92892 milliliters.
- Tablespoon (tbsp): Equals 1/2 fluid ounce or approximately 14.7868 milliliters.
- Cup: Equals 8 fluid ounces or approximately 237 milliliters.
- Pint (pt): Equals 2 cups or approximately 473.176 milliliters.
- Quart (qt): Equals 2 pints or approximately 0.946353 liters.
- Gallon (gal): Equals 4 quarts or approximately 3.78541 liters.
Mass
- Ounce (oz): Equals 1/16 of a pound or approximately 28.3495 grams.
- Pound (lb): Equals 16 ounces or approximately 0.453592 kilograms.
- Ton (T): Equals 2,000 pounds or approximately 907.185 kilograms.
Temperature
- Degrees Fahrenheit (°F): Temperature scale where water freezes at 32°F and boils at 212°F under standard atmospheric pressure.
Historical Context
The US Customary System has its roots in the British Imperial System, which was the standard in Great Britain before the adoption of the metric system. The system was brought over by early settlers and colonists and has remained in use ever since.
Applicability
The US Customary System is primarily used in everyday activities like cooking, building, and road signage. It is also prevalent in industries such as construction and manufacturing within the United States.
Comparisons to Other Systems
Metric System
The Metric System, or International System of Units (SI), is used almost universally around the world except in the United States, Liberia, and Myanmar. The metric system uses units such as meters, liters, and grams, and is based on a decimal system making it easier to convert between units.
British Imperial System
The British Imperial System is very similar to the US Customary System but has a few differences, such as the volume measurements. For example, a British Imperial gallon is larger than a US gallon.
Related Terms
- Metric System: The international system of units (SI) based on the meter, kilogram, and second.
- International System of Units (SI): The modern form of the metric system and the most widely used system of measurement.
- Imperial System: The measurement system primarily used in the United Kingdom and its former colonies.
FAQs
Why does the United States use the US Customary System?
Is the US Customary System used in scientific contexts?
What are some challenges of using the US Customary System?
References
- National Institute of Standards and Technology (NIST)
- United States Metric Association (USMA)
Summary
The US Customary System is a traditional system of weights and measures used primarily in the United States. While not as universally adopted as the metric system, it remains integral for various domestic, commercial, and industrial purposes within the country. The system includes multiple units for measuring length, area, volume, mass, and temperature, each with its unique conversion factors and applications.
