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For a uniform bar, what commonly happens to its length as temperature rises?

It usually expands, with length change related to temperature change.

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  1. It increases according to its expansion coefficient ✔
  2. It stays the same until the metal melts
  3. It shrinks as the metal softens

Why: A first approximation is that length change equals expansion coefficient times original length times temperature change. Different materials have different coefficients.

Huh, didn't know that: If expansion is restrained, temperature change can create substantial stress instead of free movement.

The dad joke
The hot bar needed more room because it was expanding its horizons.
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References

Answer: It increases according to its expansion coefficient. A first approximation is that length change equals expansion coefficient times original length times temperature change. Different materials have different coefficients.

  1. NIST Solder Properties and Thermal Expansion www.metallurgy.nist.gov/mechanical_properties/solder_paper.html
    Since a small change in temperature, dt, will cause a linearly related change in length, dl
    Checked 2026-10-10.

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