Deck 11: Reliability

Question 1

Which of the following life-test sampling plans is based on the test time

A) with replacement
B) time-terminated
C) without replacement
D) none of the above

Answer 1

B

Question 2

Two of the four conditions necessary to define reliability are:

A) numerical value and series
B) function and life
C) environment and complex
D) all of the above

Answer 2

B

Question 3

Determine the failure rate for three items that are tested to failure. Test data in
thousands of cycles are 3.2, 3.6, and 4.3.

Answer 3

0.270

Question 4

The failure pattern of a new system fits the Weibull distribution of slope 2.3 and mean life of 2.30 cycles. What is the reliability at 200 cycles

Question 5

What is the reliability of the system connected as shown below?

Question 6

Assume that on the previous problem the items that failed were replaced with new items and their replacements were still operating at the end of fifteen hours.

Question 7

What is the MTTF for Problem 3 above for a constant failure rate?

Question 8

Which of the following is used for the wear out phase

A) exponential failure analysis
B) Weibull failure analysis
C) normal failure analysis
D) all of the above

Question 9

Which of the following distributions is used in reliability analysis?

A) binomial
B) Poisson
C) hypergeometric
D) exponential

Question 10

Determine the reliability at 75 hours for a system with a constant failure rate where the mean life is 90 hours.

Question 11

Reliability is:

A) rectification
B) acceptance criteria
C) number of failures
D) quality over the long run

Question 12

The reliability of a system is the product of the individual components when they are arranged in:

A) parallel
B) series

Question 13

The reliability of a system can be improved by arranging the individual components in:

A) parallel
B) series
C) replacement
D) relays

Question 14

Tests are based on one or more of the following characteristics

A) mean life
B) hazard rate
C) reliable life
D) all of the above

Question 15

Determine the failure rate for five items that were tested for fifteen hours. Three items failed at 9, 11, 12 hours and the other two items were still operating at the end of fifteen hours.

Question 16

Construct an OC curve for a sampling plan specified as n = 15, T = 200, c = 3,
r = 6.

Question 17

One of the best ways to achieve reliability is by:

A) simplicity
B) normalizing
C) complexity
D) none of the above