From Machine Design Databook, Second Edition

SYMBOLS [3], [4], [5]


area of cross section, m 2 (in 2)

A w

area of web, m 2 (in 2)


constant in Rankine's formula


radius of area of contact, m (in) bandwidth of contact, m (in) width of beam, m (in)


distance from neutral surface to extreme fiber, m (in)


diameter of shaft, m (in)

C 1

constant in straight-line formula


load, kN (1bf)

F c

compressive force, kN (1bf)

F t

tensile force, kN (1bf)

F ?

shear force, kN (1bf)

F cr

crushing load, kN (lbf)


deformation, total, m (in) eccentricity, as of force equilibrium, m (in) unit volume change or volumetric strain

e t

thermal expansion, m (in)


modulus of elasticity, direct (tension or compression), GPa (Mpsi)

E c

combined or equivalent modulus of elasticity in case of composite bars, GPa (Mpsi)


modulus of rigidity, GPa (Mpsi)

M b

bending moment, N m (lbf ft)

M t

torque, torsional moment, N m (lbf ft)


number of turns


moment of inertia, area, m 4 or cm 4 (in 4) mass moment of inertia, N s 2 m (lbf s 2 ft)

I xx, I yy

moment of inertia of cross-sectional area around the respective principal axes, m 4 or cm 4

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SYMBOLS [2], [3] A area of cross-section, m 2 a,b coefficients b width of bar or beam, m c distance from neutral axis to extreme fibre, m velocity of propagation of plane wave along a thin bar,...

SYMBOLS a coefficients with subscripts flexibility acceleration, m/s 2 (ft/s 2) A area of cross section, m (in 2) constant B constant C coefficient of viscous damping, Ns/m or N/v (lbfs/in or...

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SYMBOLS [1], [2], [3] A area of cross section, m 2 (in 2) d diameter of shaft, m (in) diameter of cylinder, m (in) E modulus of elasticity, GPa (Mpsi) E c modulus of elasticity of cast iron, GPa...

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