# What is the relationship between centimeters millimeters meters and kilometers

### Convert km to cm

If we take 1 meter as the basic unit, we see the relationship between the metric units. The blue-shaded boxes show that 1 meter equals 10 dm, cm and millimeters. Examples. How many centimeters are kilometers? We can use . For the conversion of standard unit of length the relation between the three units are (ii) To convert kilometer (km) into meters (m), the number of km is multiplied by A very small length is measured in millimeters (mm). In between centimeter and meter there is a unit of measuring length named decimeter (dm). millimeter. mm. centimeter. cm. kilometer. km. meter. m. 10 mm = 1 cm. cm = 1 m. m = 1 km. Which is larger 1 m or 1 yard (yd). 1 m. mm = 1 m.

October Learn how and when to remove this template message Inthe French Academy of Sciences selected the meridional definition over the pendular definition because the force of gravity varies slightly over the surface of the Earth, which affects the period of a pendulum. To establish a universally accepted foundation for the definition of the metre, more accurate measurements of this meridian were needed. This portion of the meridian, assumed to be the same length as the Paris meridianwas to serve as the basis for the length of the half meridian connecting the North Pole with the Equator.

The problem with this approach is that the exact shape of the Earth is not a simple mathematical shape, such as a sphere or oblate spheroidat the level of precision required for defining a standard of length. The irregular and particular shape of the Earth smoothed to sea level is represented by a mathematical model called a geoidwhich literally means "Earth-shaped". Despite these issues, in France adopted this definition of the metre as its official unit of length based on provisional results from this expedition.

However, it was later determined that the first prototype metre bar was short by about micrometres because of miscalculation of the flattening of the Earth, making the prototype about 0.

Regardless, this length became the French standard and was progressively adopted by other countries in Europe. This new organisation was to construct and preserve a prototype metre bar, distribute national metric prototypes, and maintain comparisons between them and non-metric measurement standards.

## Basic Math for Adults/Measurements

Wavelength definition[ edit ] Inthe standard metre was first measured with an interferometer by Albert A. Michelsonthe inventor of the device and an advocate of using some particular wavelength of light as a standard of length.

**Common metric units of length: kilometers, meters, centimeters & millimeters (3rd grade math)**

Byinterferometry was in regular use at the BIPM. An intended by-product of the 17th CGPM's definition was that it enabled scientists to compare lasers accurately using frequency, resulting in wavelengths with one-fifth the uncertainty involved in the direct comparison of wavelengths, because interferometer errors were eliminated.

To further facilitate reproducibility from lab to lab, the 17th CGPM also made the iodine-stabilised helium—neon laser "a recommended radiation" for realising the metre. When converting from a smaller unit, such as feet, to a larger unit, such as yards, students divide. To convert 48 feet into yards, students look at the table of equivalencies to find that 1 yard equals 3 feet. Students may have difficulty remembering when to multiply and when to divide. If so, have them think about whether there will be more or less of the unit they are converting to than of the unit they are converting from.

If there will be more of the new unit, they must multiply. If there will be less, they must divide. Students will review the customary units of capacity and weight, converting among customary units. Students should be familiar with the measures of cups, pints, quarts, and gallons, and the measures of ounces and pounds.

This is the first time they will have worked with tons. As with linear measure, to convert between units of capacity or weight, students must look up the unit equivalencies and then decide whether to multiply or divide. Students review the metric system by actually measuring objects to the nearest centimeter and millimeter. Then they progress to finding perimeter in meters and kilometers and to converting between millimeters, centimeters, decimeters, meters, and kilometers.

At this point students will not work with dekameters or hectometers. Converting units within the metric system is much simpler than within the customary system. Because the metric system is a base-ten system, students simply need to multiply or divide by powers of ten to convert.

### Metre - Wikipedia

They can look up the equivalencies in the tables provided in their student book. They then multiply or divide by the appropriate power of ten, depending upon whether they are converting from larger units to smaller units or from smaller units to larger units. Since the same prefixes are used to measure length, capacity, and weight, students may come to understand the relationship between the prefixes and not need to look up the equivalencies. Students progress to converting between metric units of capacity and mass.

Although the terms mass and weight are often used interchangeably, they do have different meanings.

Mass is the amount of matter in an object. Weight measures the force of the Earth's gravity acting upon the mass of an object.