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Unit Definitions

Simscape™ unit names are defined in the pm_units.m file, which is shipped with the product. You can open this file to see how the physical units are defined in the product, and also as an example when adding your own units. This file is located in the folder matlabroot\toolbox\physmod\common\units2\mli\m.

Default registered units and their abbreviations are listed in the following table. Use the pm_getunits command to get an up-to-date list of units currently defined in your unit registry. Use the pm_adddimension and pm_addunit commands to define additional units.

Physical Unit Abbreviations Defined by Default in the Simscape Unit Registry

QuantityAbbreviationUnit
Acceleration

gee

Earth gravitational acceleration (9.80665 m/s^2)

Amount of substance

mol

Mole

Angle

rad

deg

rev

Radian

Degree

Revolution

Angular velocity

rpm

Revolutions/minute

Capacitance

F

pF

nF

uF

Farad

Picofarad

Nanofarad

Microfarad

Charge

C

nC

uC

mC

Ah

mAh

kAh

MAh

Coulomb

Nanocoulomb

Microcoulomb

Millicoulomb

Ampere-hour

Milliampere-hour

Kiloampere-hour

Megaampere-hour

Conductance

S

nS

uS

mS

Siemens

Nanosiemens

Microsiemens

Millisiemens

Current

A

pA

nA

uA

mA

kA

MA

Ampere

Picoampere

Nanoampere

Microampere

Milliampere

Kiloampere

Megaampere

Energy

J

uJ

mJ

kJ

MJ

Wh

mWh

kWh

MWh

Btu_IT

eV

Joule

Microjoule

Millijoule

Kilojoule

Megajoule

Watt-hour

Milliwatt-hour

Kilowatt-hour

Megawatt-hour

British thermal unit

Electronvolt

Flow rate

lpm

gpm

Liter/minute

Gallon/minute

Force

N

dyn

lbf

mN

Newton

Dyne

Pound-force

Millinewton

Frequency

Hz

kHz

MHz

GHz

Hertz

Kilohertz

Megahertz

Gigahertz

Inductance

H

uH

mH

Henry

Microhenry

Millihenry

Length

m

cm

mm

km

um

in

ft

mi

yd

Meter

Centimeter

Millimeter

Kilometer

Micrometer

Inch

Foot

Mile

Yard

Magnetic flux

Wb

Weber

Magnetic flux density

T

G

Tesla

Gauss

Mass

kg

g

mg

t

lbm

oz

slug

Kilogram

Gram

Milligram

Tonne (metric ton)

Pound mass

Ounce

Slug

Pressure

Pa

uPa

kPa

MPa

GPa

bar

kbar

atm

psi

ksi

Pascal

Micropascal

Kilopascal

Megapascal

Gigapascal

Bar

Kilobar

Atmosphere

Pound/inch^2

Kilopound/inch^2

Power

W

uW

mW

kW

MW

HP_DIN

Watt

Microwatt

Milliwatt

Kilowatt

Megawatt

Horsepower

Resistance

Ohm

mOhm

kOhm

MOhm

GOhm

Ohm

Milliohm

Kiloohm

Megaohm

Gigaohm

Temperature

K

degC

degF

degR

deltaK, deltadegC, deltadegF, deltadegR

Kelvin

Celsius

Fahrenheit

Rankine

Relative temperature units (see Thermal Unit Conversions)

Time

s

min

hr

d

ms

us

ns

Second

Minute

Hour

Day

Millisecond

Microsecond

Nanosecond

Velocity

mph

fpm

fps

Miles/hour

Feet/minute

Feet/second

Viscosity absolute

P

cP

reyn

Poise

Centipoise

Reyn

Viscosity kinematic

St

cSt

newt

Stokes

Centistokes

Newt

Volume

l

gal

igal

Liter

US liquid gallon

Imperial (UK) gallon

Voltage

V

mV

kV

MV

Volt

Millivolt

Kilovolt

Megavolt

Note

This table lists the unit abbreviations defined in the product. For information on how to use the abbreviations above, or mathematical expressions with these abbreviations, to specify units for the parameter values in the block dialogs, see How to Specify Units in Block Dialogs.