The method
Before using the result
- Uniform temperature change, constant user-supplied coefficient and free unrestrained expansion. Restraint stresses are not calculated.
Worked examples
These original training examples illustrate the method for United States: Fundamentals of Engineering (FE) Examination. Use the matching “Load example” button above to explore a variation; example values are not equipment settings or prescribed criteria.
1. Worked example
Track the sign of free thermal movement in a mechanics or heat-transfer problem. Keep movement calculations separate from restraint stress and expansion-joint design.
- Original length
- 10 m
- Linear expansion coefficient (1/K)
- 0.000012
- Temperature change
- 50 K
- ΔL = 0.000012 × 10 × 50 = 0.006 m.
- Length change: 0.006 m
- Final length: 10.006 m
2. Comparison example
Compare a different supplied condition using the same method. For Engin Exam, the important check is that the input meaning, units and method assumptions still match the problem.
- Original length
- 10 m
- Linear expansion coefficient (1/K)
- 0.000012
- Temperature change
- -30 K
- ΔL = 0.000012 × 10 × -30 = -0.0036 m.
- Length change: -0.0036 m
- Final length: 9.9964 m
Check your understanding
1. Which relationship is used?
ΔL = αLΔT; final length = original length + ΔL.
2. Which assumption should you check first?
Uniform temperature change, constant user-supplied coefficient and free unrestrained expansion. Restraint stresses are not calculated.
3. How should you verify a different unit system?
Convert every input to the displayed calculation units first. Equivalent physical inputs must give equivalent results; a unit label alone does not convert a number.
Continue with the matching exam topic
This tool connects to United States: Fundamentals of Engineering (FE) Examination free practice. Work through a question independently, then use the calculation steps to identify where your method differs. The tool stays free whether or not you choose paid preparation.