# You answered my question as yes someone answered no . I need correct answer for the question is kilometer is SI unit of length?

Jun 20, 2018

No kilometre is not an SI unit.

#### Explanation:

The SI unit of length is the metre. The prefix kilo means 1,000. So, a kilometre is 1,000 metres. Most SI units have an exact value which can be modified by a prefix to multiply or divide it by powers of ten.

The one exception to this is the kilogram which is an SI unit complete with the kilo prefix. The reason for this being that the SI system is derived from the MKS=metre, kilogram, second system which replaced the CGS=centimetre, gramme, second systems of units.

Jun 29, 2018

The meter is an SI unit.

#### Explanation:

The meter is an SI unit -- in fact it one of the SI system's 7 base units which are used to define the derived SI units. The newton is an example of of a derived SI unit.

Example of base units being used to define derived a derived unit:

The $\text{newton}$ is defined to be equivalent to $\frac{k g \cdot m}{s} ^ 2$

The kilogram (kg), meter (m) and second (s) are each one of the 7 SI base units.

I hope this helps,
Steve

Jun 29, 2018

SI unit of length is $\textcolor{red}{\text{METER}}$

#### Explanation:

Kilometer is just another unit by which length or distance is measured.

But according to International system of units, METER is the SI unit of distance.

Jun 29, 2018

No, it is not.

#### Explanation:

SI, the International System of Units (french is Système International d'Unités), includes seven base units ampere, kelvin, second, meter, kilogram, candela and mole. Hence kilometer is not SI unit.

There are also derived units such as watt, which can be derived from kilogram (mass), meter (distance) and second (time) and watt is kg*m^2*s^(−3). Kilometer is just $1000$ meters and we cannot term it as derived unit. It is just another unit of length and is $1000 m$.