Page 28 - Singiresu S. Rao-Mechanical Vibrations in SI Units, Global Edition-Pearson (2017)

LISt oF SyMBoLS 25

Symbol Meaning SI Units

r > frequency ratio = v>v n
r radius vector m
Re( ) real part of ( )
R(t ) autocorrelation function
R electrical resistance ohm
#
R Rayleigh’s dissipation function N m>s
R Rayleigh’s quotient l /s 2
s root of equation, Laplace variable
S a , S d , S v acceleration, displacement, velocity spectrum
S x 1v2 spectrum of x
t time s
t i ith time station s
T torque N-m
T kinetic energy J
T i kinetic energy of ith mass J
T d , T f displacement, force transmissibility
u ij an element of matrix [U]
U,U i axial displacement m
U > potential energy J
U unbalanced weight N
[U] upper triangular matrix
v, v o linear velocity m/s
V shear force N
V potential energy J
V i potential energy of ith spring I
w, w 1 , w 2 , v i transverse deflections m
W 0 value of w at t = 0 m
#
#
w 0 value of w at t = 0 m/s
w n nth mode of vibration
W weight of a mass N
W total energy J
W transverse deflection m
W i value of W at t = t i m
W(x) a function of x
x, y, z cartesian coordinates, displacements m
x 0 , x(0) value of x at t = 0 m
#
#
#
x 0 , x102 value of x at t = 0 m/s
x j displacement of jth mass m
x j value of x at t = t j m
#
#
x j value of x at t = t j m/s
x h homogeneous part of x(t) m