4-7. Two random forces 
and
act on a beam as in the
figure. The
allowable bending stress of the beam is
. 
,
and 
are
independent. Determine the probability of failure of the beam. (Ans.
)
4-7. Two random forces and act on a beam as in the
figure. The
allowable bending stress of the beam is
. ,
and are
independent. Determine the probability of failure of the beam. (Ans.
)