Question

The C.G.S unit of length is _____

Answer 1

Length is a measure of distance from one point to the other.
The Centimetre-Gram-Seconds (C.G.S) system uses three fundamental quantities length, mass and time.

Complete step by step solution:
Unit is a definite magnitude of a quantity, adopted universally.
Length is a fundamental quantity.
The C.G.S system of units uses the fundamental unit of length as centimetre (cm).

Additional information:
As different units of measurement, a standard universal unit was needed for convenience.
The Standard International (S.I) unit of measurement of length is metre (m).
In 1889, The International Bureau of Weight and Measures, defined metre as “the distance between two lines on a standard bar of an alloy of platinum with $10$ iridium, measured at the melting point of ice.”
In $1983$ , The International Bureau of Weight and Measures fixed the length of the metre in terms of the second and the speed of light as:
“The metre is the length of the path travelled by light in vacuum during a time interval of $\dfrac{1}{299792458}$ of a second.”
To measure larger distances , bigger units were needed.
Some of the bigger units of length are:

& 1\text{ km}=1000\text{ m} \\\ & \text{1 AU}\approx \text{150,000,000,000 m} \\\ \end{aligned}$$ The astronomical unit AU is used to measure the distance of stars and planets. Sub-unit of length are: $$\begin{aligned} & 1\text{ nm}={{10}^{-9}}\text{ m} \\\ & \text{1 }\mu \text{m}={{10}^{-6}}\text{ m} \\\ \end{aligned}$$ The sub-units are used to measure the wavelength of various spectrums of white light. **Note:** The S.I. and C.G.S unit of length are related as: $$1\text{ m}=100\text{ cm}$$ The various units of length are inter-convertible. Although the length of any object is definite, but if the object moves with a velocity comparable to light, its length decreases.