Millimetre

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Millimetre (International spelling as used by the SI; American spelling: millimeter) is a unit of length in the metric system, equal to one thousandth of a metre (the SI base unit of length). The symbol for millimetre is mm.

Definition

A millimetre is defined as 1/1000 of a metre, which is the base unit of length in the SI. This means that there are 1,000 millimetres in a metre.

Usage

Millimetres are commonly used in many fields, including engineering, architecture, and manufacturing, where precise measurements are crucial. They are also used in everyday measurements, such as the thickness of a credit card or the dimensions of small objects.

Conversion

One millimetre is equivalent to:

• 0.1 centimetre (cm)
• 0.001 metre (m)
• 0.0393701 inch (in)

Applications

Millimetres are used in various applications:

• In engineering, for specifying the dimensions of components.
• In medicine, for measuring small distances and sizes, such as the thickness of tissues or the size of medical devices.
• In science, for precise measurements in experiments and research.

Related Units

• Micrometre (µm) - One thousandth of a millimetre.
• Centimetre (cm) - One hundredth of a metre.
• Metre (m) - The base unit of length in the SI.

See Also

• Metric system
• International System of Units
• Length
• Measurement