Meters to Centimeters Converter

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Meter

What is the meter?

The meter is the base unit of length in the SI unit system, which is the current standard of the metric system. It is used to measure the lengths of medium to large objects and distances that are not too long. We have been using different scales and tools to measure lengths and distances in meters, but how was it defined and determined how long a meter would be? Let's find out in the next section.

History of the meter

From ancient times, we have been measuring the length of objects. The earliest known measurement methods used the lengths of our body parts, such as the foot, hands, fingers, arms, etc. However, these methods needed more accuracy and precision due to the differences in the size of human body parts from person to person. Thus, the idea of building a universal measurement system arose in France.

To achieve this, a council of scientists and mathematicians established by the French Academy of Sciences proposed a decimal-based measurement system in 1791. As per recommendations, the units of various quantities like length, volume, and mass were defined. The name meter was borrowed from the Greek word metron, meaning "a measure". The meter length was determined as the ten-millionth of the distance of the line between the North Pole and the equator, passing through Paris in France.

To realize this definition, a geodetic survey was conducted between 1792 and 1798 between Dunkirk, France, and Barcelona, Spain. The final measurement was submitted to the academy in 1799, and a platinum bar was embodied based on this measurement to define the length of a meter. This newly defined system of measurements, introduced in France, was called the metric system and was gradually adopted in other parts of the world.

In 1875, the Treaty of the Meter was signed by 17 countries, including the United States. As a result, the International Bureau of Weights and Measures (BIPM) was established.

In 1889, a new meter prototype, a bar made of platinum and iridium with an X-shaped cross-section, was developed for better durability and adopted as the international prototype of the meter. The length of the meter was determined by the distance between two endpoints of this platinum-iridium bar at the standard atmospheric pressure at the melting point of ice.

In 1960, the definition of the meter was again changed. The length of a meter was defined as 1,650,763.73 wavelengths in the vacuum of the radiation corresponding to the transition between certain levels of a krypton 86 atom. This was when the metric system was changed to its current standard, the International System of Units (SI).

Note that every time the meter is redefined, the actual length of the meter remains unchanged. These changes in the meter definition are made to avoid any challenges that may arise in the future in sustaining the original meter length. For example, the platinum bar initially embodied to realize the meter length could have been damaged, lost, or stolen in the future. In that scenario, a solid definition of the meter was required so that anyone could easily create a meter prototype using that definition.

The meter was again redefined in 1983 based on the speed of light to achieve more accuracy. Keeping the same meter prototype as the reference, scientists noted that the light in a vacuum travels the exact distance equal to the length of a meter in 1/299,792,458 seconds, and that was made the standard definition of the meter. This also defined the speed of light in a vacuum as 299,792,458 meters per second. The 1983 definition is the most accurate definition of the meter so far and is still in use.

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Centimeter

What is the centimeter?

The centimeter is a unit of length in the SI unit system. Like inches, it is also used to measure the lengths of smaller objects or small distances. The centimeter is a smaller unit of meter that values one-hundredth of a meter. The centimeter is symbolized as cm.

History of the centimeter

The roots of the centimeter lie in the French metric system, defined in the late 18th century. The word centimeter was taken by combining the Latin word “centum” meaning a hundred, and the French word “mètre” meaning meter. It does not mean a hundred meters equals one centimeter, but it means exactly the opposite, that is, one hundred centimeters make one meter. The centimeter was the base unit in the now-deprecated CGS (Centimeter-Gram-Second) unit system, which was based on the metric system.

How long is a centimeter?

Compared to inches, a centimeter is approximately 0.3937 inches long. However, by looking at some day-to-day objects around us, we can get an idea of how long a centimeter is.

For example,

• The width of a fingernail is about one cm.
• A small marble's diameter is about one cm.
• Some small capsule pills have a length of one cm.

Measurements that use the centimeter as the unit of length

Several standard measurements use the centimeter as their unit.

• Height Measurement Height is frequently measured in centimeters, especially in countries that have adopted the metric system.
• Furniture DimensionsFurniture dimensions such as table height and width, chair seat height, sofa length, etc. are usually measured in centimeters.
• Clothing SizesTailors and garment manufacturers measure body dimensions in centimeters.
• Electronics and Gadgets The dimensions of small electronics, like the screen size of phones and tablets, are often specified in centimeters.
• A4 Paper Size In some countries, paper sizes are measured in centimeters. For example, A4-sized paper is 21 cm by 29.7 cm.
• JewelryNeckless lengths, bracelet sizes, and ring diameters can be measured in centimeters.
• Books Dimensions The dimensions of books, particularly their height and width, are often given in centimeters.
• Photographs The sizes of printed photographs can be measured in centimeters, such as a standard 10 cm by 15 cm print.

Standard measurement sizes in centimeters

• A4 PaperA standard sheet of A4 paper measures 21 x 29.7 cm.
• PhotographsStandard photo sizes, such as 10 x 15 cm (4 x 6 inches), 13 x 18 cm (5 x 7 inches), etc.
• Business Cards A typical business card measures 8.9 x 5.1 cm.
• CD and DVD CasesStandard cases for CDs and DVDs are about 19 x 13.5 x 1.4 cm (length x width x thickness).
• PostcardsStandard postcard sizes are often around 14.8 x 10.5 cm.
• Envelope standard envelope sizes, like the DL envelope, which is 11 x 22 cm.
• Lego BrickThe standard 2 x 4 Lego brick measures 3.2 x 1.6 x 1.1 cm.
• Standard Brick The standard size of brick used in construction is usually 9.2 x 5.7 x 19.4 cm (width x height x length).
• Passport PhotoThe standard size for a passport photo in the USA and India is 5.1 x 5.1 cm, 3.5 x 4.5 cm in the UK, Europe, Australia, Singapore, Nigeria, and many other countries, 5 x 7 cm in Canada, and 3.3 x 4.8 cm in China.

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Frequently Asked Questions