Sample CRE Questions

 1. Estimate the individual part failure rate given a base failure rate of  0.0333 failure/hour, a quality factor of 0.98 and an environmental stress factor …

1. The  lifetime  of  a  mechanical  lifter  is  normally  distributed  with  a  mean  of  100  hours  and  a  standard deviation of 3 hours. What is …

1. The effects of failure rates on increased temperatures is called the: a. Thermal model b.  Full scale Model  c. Arrhenius Model   d. Derating effects …

1. Given the density function obtained  under accelerated conditions:  Determine the density function under normal operating conditions,  given an acceleration factor of 5  a. (1/150)exp(-t/150)  b.(1/6)exp(-t/6) …

1. Three components in parallel have mean times to failure of 50, 60, & 70 hrs respectively. The mean repair times are 30, 40 & …