Kilometer (km)

Definition

The kilometer (km) is a unit of length in the International System of Units (SI). It is defined as exactly 1,000 meters.

History

The kilometer was first adopted in France in the late 18th century during the French Revolution. The metric system was established in 1795, with the kilometer becoming a standard unit for measuring distance. The term "kilometer" combines the Greek prefix "kilo-" (meaning one thousand) with the meter.

Uses

Kilometers are commonly used in everyday life for measuring distances between locations, especially in countries that utilize the metric system. It is widely used in scientific applications, engineering, and transportation. Most countries, except for the United States, use kilometers for road signage and distance calculations.

Conversions

• 1 kilometer = 1,000 meters
• 1 kilometer = 0.621371 miles
• 1 kilometer = 100,000 centimeters

Fun Facts

• A common misconception is that the kilometer is a non-metric unit, but it is indeed part of the SI system.
• The kilometer is often used in sports, such as running races, where distances are frequently measured in kilometers rather than miles.