TABLE OF CONTENTS | A | area of cross section, m 2 (in 2) | |
| A w | area of web, m 2 (in 2) | |
| a | constant in Rankine's formula | |
| b | radius of area of contact, m (in) bandwidth of contact, m (in) width of beam, m (in) | |
| c | distance from neutral surface to extreme fiber, m (in) | |
| D | diameter of shaft, m (in) | |
| C 1 | constant in straight-line formula | |
| F | 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) | |
| e | deformation, total, m (in) eccentricity, as of force equilibrium, m (in) unit volume change or volumetric strain | |
| e t | thermal expansion, m (in) | |
| E | modulus of elasticity, direct (tension or compression), GPa (Mpsi) | |
| E c | combined or equivalent modulus of elasticity in case of composite bars, GPa (Mpsi) | |
| G | modulus of rigidity, GPa (Mpsi) | |
| M b | bending moment, N m (lbf ft) | |
| M t | torque, torsional moment, N m (lbf ft) | |
| i | number of turns | |
| I | 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 |
