1.Discrete random variable, X, follows the following probability distribution:
What is the Mean, Std Dev?
A. 1.65, 13.4
B. 1.65, 3.65
C. 3.55,1.65
D. Not A,B, or C
2. Given a part with Strength distribution Normal (25,6) and a Stress distribution Normal (10,6), what is the Reliability?
A. 0.975
B. 0.610
C. 0.961
D. ~0.75
3. Which one of the following is NOT a description of Reliability Engineer’s
responsibilities regarding product safety?
A. Coordinate safety compliance tests
B. Perform root cause analysis and coordinate corrective action for safety test findings
C. Apply and complete safety agency certificates
D. None of the above
4. Which of the following failure modes is not usually caused by material subjected to high or low temperatures?
A. Softening and weakening
B. Chemical changes
C. Mold growth
D. Reduced viscosity
5. The use of stress‐strength analysis in modern DFR (design for reliability) is an example of:
A. Deterministic design
B. Probabilistic design
C. Data mining design
D. Design for maintainability
6. In a design FMEA activity, the use of a design verification test to verify proper function over expected life is an example of which of the following?
A. Prevention design control
B. Detection design control
C. Both a prevention and a detection design control
D. Compensatory design control
7. The intent of a recommended action in a Design Failure Mode Effects Analysis (DFMEA) is to reduce rankings in which of the following orders of priority?
A. Severity, Occurrence, Detection
B. Occurrence, Severity, Detection
C. Severity, Detection, Occurrence
D. Occurrence, Detection, Severity
8. A cargo ship’s navigation system includes two identical Global Positioning System (GPS) units. The secondary unit is in standby mode and is employed only in the event that the primary GPS unit fails. What is the 500‐hour reliability of the navigation system if each GPS unit has a failure rate of 0.00005 failures/hour and the switch over to the secondary system is considered to have a reliability of 1?
A. 0.9994
B. 0.9512
C. 0.9350
D. 0.9997
9. Which of the following best describes a limitation of Parts Count Reliability Prediction?
A. Some failure modes are not due to part (component) failures.
B. Parts used in the design may be newer technology.
C. Specific customer usage or environmental profiles are not fully considered.
D. All of the above
10. Failure mechanisms in which three of the following would most likely be found through random vibration testing?
I. Fatigue II. Heat sink mounting III. Large component mounting IV. Circuit design margin
A. I, II & III
B. I, II & IV
C. I, III & IV
D. II, III & IV
