Reliability
What is the mean time to failure (MTTF) of a part with a constant failure rate of 1×10⁻⁵ per hour?
- A1×10³ hours
- B1×10⁵ hours
- C1×10⁷ hours
Show answer and explanation
Answer: B. 1×10⁵ hours
When the failure rate is constant, mean time to failure is its reciprocal: 1 ÷ (1×10⁻⁵) = 1×10⁵ hours, about 11 years. However, this value applies to the random failure period and does not indicate when wear-out begins.