NOTATION Quantity Symbol SI Unit Angle xB,8,中 rad (radian) Length L,s m (metre) mm (millimetre) Area A m2 Volume V m3 Time t s (second) Angular velocity 0 rad/s Velocity v m/s Weight W N(newton) Mass m kg (kilogram) Density kg/m3 Force F ot P or W N Moment M Nm Pressure P Pa (Pascal) N/m2 bar(=105N/m2) Stress N/m2 Strain Shear stress N/m2 Shear strain Y Young's modulus E N/m2 Shear modulus G N/m2 Bulk modulus K N/m2 Poisson's ratio Modular ratio m Power W(watt) Coefficient of linear expansion m/m C Coefficient of friction 4 Second moment of area m4 Polar moment of area J m Product moment of area m Temperature T C Direction cosines 1,m,n Principal stresses 01,02,03 N/m2 Principal strains e1,e2,e3 Maximum shear stress N/m2 Octahedral stress oct N/m2 xViiNOTATION Quantity Angle Length Area Volume Time Angular velocity Velocity Weight Mass Density Force Moment Pressure Stress Strain Shear stress Shear strain Young's modulus Shear modulus Bulk modulus Poisson's ratio Modular ratio Power Coefficient of linear expansion Coefficient of friction Second moment of area Polar moment of area Product moment of area Temperature Direction cosines Principal stresses Principal strains Maximum shear stress Octahedral stress A V t 0 V W m P F or P or W M P 0 E z Y E G K m V Si Unit rad (radian) m (metre) mm (millimetre) mz m3 s (second) rad/s m/s N (newton) kg (kilogram) kg/m3 N Nm Pa (Pascal) N/m2 bar ( = lo5 N/m2) N/m2 N/m2 N/m2 N/m2 N/m2 - - - - W (watt) m/m "C m4 m4 m4 "C N/m2 N/mz N/mZ - - - xvii