Question
The negative ratio of two forms of this quantity gives Poisson's ratio, which is negative for auxetic metamaterials. For 10 points each:
[10m] Name this quantity that, in mechanics, equals the ratio of the change in length to initial length.
ANSWER: strain [accept characteristic strain or axial strain or transverse strain; prompt on epsilon]
[10h] This scientist and Green name an object in infinitesimal strain theory that is calculated from the deformation gradient and its transpose. This scientist also names a "second-order" object that yields T when dotted with a normal vector.
ANSWER: Augustin-Louis Cauchy ("koh-SHEE") (The objects are the Cauchy–Green deformation tensor and the Cauchy stress tensor.)
[10e] Because strain equals a ratio of two lengths, it has this property in dimensional analysis that is also possessed by the Reynolds number. A description is acceptable.
ANSWER: unitless [accept descriptions of no units or not having units; prompt on dimensionless or dimension one]
<Science - Physics>
Data
Summary
| Tournament | Edition | Exact Match? | Heard | PPB | Easy % | Medium % | Hard % |
|---|---|---|---|---|---|---|---|
| 2025 PACE NSC | 06/07/2025 | Y | 33 | 9.70 | 76% | 15% | 6% |