Page 301 - Mechanical Engineer's Data Handbook

GENERAL DATA 289

Quantity Symbol Unit Quantity Symbol Unit

Inertia. moment of I. J kg m2 Reluctance S H, A Wb-'
Relative density d No unit
Kinematic viscosity Y m2 s- ', St
Resistance, electrical R R
Length I m Resisting force R N
Light: velocity of c ms-' Resistance, temperature 2, B. 7 C-I
Light, wavelength of /. m coefficients of
Linear expansion, 3 oc-l Resistivity: conductors P Ma-mm
coefficient of insulators P Ma-mm
Luminance L cdm-2 Resonant frequency f, Hz
Luminous flux 4 Im Second moment of area
Luminous intensity I cd I m4
Self-inductance L H
Magnetic field strength H Am-' Shear strain I No unit
Magnetic Hux @ Wb Shear stress 5 Nm-2, Pa
Magnetic Hux density B T Specific gas constant R kJkg-'K-'
Magnetomotive force F A Specific heat capacity C kJkg-'K-'
Mass: m kg Specific volume \' m3kg-l
Mass: rate of How k kgs-l Strain, direct E No unit
Modulus, bulk K Nm-2 Stress, direct U Nm-2, Pa
Modulus of elasticity E Nm-' Shear modulus of G NrW2, Pa
Modulus of rigidity G N m-2 rigidity
Modulus of section z m3 Surface tension Nm-'
Molar mass of gas M kg K -' mol-I Susceptance B S
Molar volume vm m3 K-' mol-' Temperature value
Moment of force M N-m 0 'C
Moment of inertia I, J kg-m2 Temperature coefficients a, fi, 7 C'
Mutual inductance M H of resistance
Thermodynamic T K
Number of turns in a N No unit temperature value
winding Time t b
Torque T Nm
Periodic time T
Permeability: absolute 1' Vapour velocity C rns-'
absolute of PO Velocity V ms-l
free space Velocity, angular w rads-'
relative Pr angular N revk
Permeance A H rev/min
Permittivity, absolute E pFm-' Velocity of light C ms-'
Permittivity of free space EO pFm-' Velocity of sound CY ms-'
Permittivity, relative E, No unit Voltage V V
Poisson's ratio \' No unit Volume V m3
Polar moment of area J m4 Volume, rate of flow V m3s1'
Power: apparent S V-A Viscosity: dynamic P. 'J Nsm-2, cP
active P W kinematic Y m2s-I, cst
reactive Q V-A,
Pressure P Nm-2, Pa Wavelength 1. W m
Work
J
Quantity of heat Q J Young's modulus of E
Quantity of electricity Q A-h, C elasticity Nm-2. Pa
Reactance X R