32.
A toque 
is applied to the central
portion of the span of a torsion bar. The bar has a round cross section with a diameter
and has a lenghth of 
. The shear modulus of the bar is
. What is the mean and standard
deviation of the spring rate using the First Order Second Moment Method? Assume
that 
, 
and
are independent.
Answer: 
, 