Abstract
We study the joint probability distribution of normal and tangential frictional forces in jammed granular media,
P
μ
(
f
t
,
f
n
)
, for various values of the friction coefficient
μ
, especially when
μ
=
∞
. A universal scaling law is found to collapse the data for
μ
=
0
to
∞
, demonstrating a link between the force distribution
P
μ
(
f
t
,
f
n
)
and the average coordination number,
z
c
μ
. The results determine
z
c
μ
for a finite friction coefficient, extending the constraint-counting argument of isostatic granular packing to finite frictional packings.
