The time dependence of the remanent coercivity for noninteracting Stoner-Wo
hlfarth particles with uniaxial anisotropy has been calculated numerically
as a function of easy axis angle and distribution width. The results have b
een interpreted in terms of a simplified effective energy barrier function
of the form DeltaE = CKV(1 - H/Ho)(n) and a modified Sharrock equation, For
a system with identical easy axis angles, Sharrock law behavior occurs at
all angles over a wide range of times with C = 1 and n a function of angle.
For a distribution of easy axes, Sharrock law behavior also occurs with C
= 1 and n approximate to 1.5 for squareness values ranging from random to a
t least 0.98. The dependence of the energy barrier on field and easy axis a
ngle is compared with the Victora expansion and with the Pfeiffer model.