Systems of Measurement and Unit Conversions Flashcards

Vocabulary flashcards covering systems of measurement, units, definitions, historical body-part bases, time, and area.

System of Measurement

A standardized set of units and rules used to quantify physical quantities.

Metric System of Measurement

Also known as the International System of Units (SI), it is the standard measurement system used in most countries worldwide and is a decimal-based system that uses base units like the meter (length), the gram (mass), and the liter (volume).

US Customary System

A measurement system primarily used in the United States that uses traditional units not based on tens (such as inches, feet, yards, miles, pounds, and gallons), making conversions trickier.

Length

A reference standard for measuring distance or the size of an object in one dimension.

Mass

Measures the amount of matter in an object.

Volume / Capacity

A measure of three-dimensional space an object occupies or a container holds.

Area

Measures the two-dimensional space covered by a surface, with units being squares of a linear measurement, such as square meters ($\text{m}^2$) or square feet ($\text{ft}^2$).

Inch (in)

An English measurement unit historically based on the width of a person's thumb, equal to about $2.54\,\text{cm}$.

Palm

An English measurement unit based on the width of the palm, equal to about $3\,\text{inches}$.

Hand

An English measurement unit based on the width of four fingers, equal to $4\,\text{inches}$.

Span

An English measurement unit based on the distance from the tip of the thumb to the tip of the little finger when the hand is fully stretched, equal to about $9\,\text{inches}$.

Foot (ft)

An English measurement unit based on the length of a person's foot, equal to $12\,\text{inches}$.

Cubit

An English measurement unit defined as the distance from the elbow to the tip of the middle finger, equal to about $18\,\text{inches}$.

Yard (yd)

An English measurement unit traditionally believed to be the distance from the nose to the tip of the outstretched middle finger of King Henry, equal to $3\,\text{feet}$.

Fathom

An English measurement unit defined as the distance between the tips of the fingers when both arms are stretched out, equal to $6\,\text{feet}$.

Millisecond (ms)

A metric unit of time equal to $\frac{1}{1,000}$ of a second ($1\,\text{ms} = 0.001\,\text{s}$).

Microsecond ($\mu\text{s}$)

A metric unit of time equal to $\frac{1}{1,000,000}$ of a second ($1\,\mu\text{s} = 0.000001\,\text{s}$).

Nanosecond (ns)

A metric unit of time equal to $\frac{1}{1,000,000,000}$ of a second ($1\,\text{ns} = 10^{-9}\,\text{s}$).

Kilosecond (ks)

A metric unit of time equal to $1,000\,\text{seconds}$ ($16\,\text{min } 40\,\text{sec}$).

Second (s)

The base unit of time in both the metric and customary systems.