Definition:Unit of Measurement

This page is about unit of measurement. For other uses, see unit.

Definition

A unit of measurement is a specified magnitude of a given physical quantity, defined by convention.

It is used as a standard for measurement of that physical quantity.

Any other value of the physical quantity can be expressed as a multiple of that unit of measurement.

Examples

Mass

The physical quantity mass can be defined by specifying how two bodies are compared using a balance.

The mass of one of the bodies can be taken as a standard, and given a name, for example kilogram or pound.

Then the mass of any other body can be expressed in terms of this unit of measurement.

Also known as

Some sources refer to a unit of measurement as a unit of measure.

Also see

• Definition:Fundamental Unit (Physics)
• Definition:Dimension of Measurement

• Results about units of measurement can be found here.

Sources

• 1921: C.E. Weatherburn: Elementary Vector Analysis ... (previous) ... (next): Chapter $\text I$. Addition and Subtraction of Vectors. Centroids: Definitions: $1$. Scalar and vector quantities
• 1944: Alfred E. Holbrow: Geometrical Drawing (12th ed.) ... (previous) ... (next): Section $\text I$. Introduction
• 1951: B. Hague: An Introduction to Vector Analysis (5th ed.) ... (previous) ... (next): Chapter $\text I$: Definitions. Elements of Vector Algebra: $1$. Scalar and Vector Quantities
• 1964: D.E. Rutherford: Classical Mechanics (3rd ed.) ... (previous) ... (next): Chapter $\text I$: Kinematics: $1$. Space and Time
• 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): physical quantity
• 1998: David Nelson: The Penguin Dictionary of Mathematics (2nd ed.) ... (previous) ... (next): unit: 1.
• 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): physical quantity
• 2008: David Nelson: The Penguin Dictionary of Mathematics (4th ed.) ... (previous) ... (next): unit: 1.
• 2014: Christopher Clapham and James Nicholson: The Concise Oxford Dictionary of Mathematics (5th ed.) ... (previous) ... (next): unit