Question
Auxetic materials are metamaterials with negative values of this property, which are often designed as lattices of polygonal cells. For 10 points each:
[10m] Give this mechanical property. Materials with negative values of this property can be used to create one-size-fits-all clothing, since they get longer and wider when they are stretched.
ANSWER: Poisson’s ratio [or Poisson ratio; accept negative Poisson’s ratio]
[10h] One of the most-studied 2D auxetic structures is the “re-entrant” variant of these structures. These structures name the lattice used in the Kitaev model of quantum spin liquids.
ANSWER: honeycombs [accept re-entrant honeycomb or honeycomb lattice]
[10e] Poisson’s ratio is defined as the negative ratio of this quantity along the transverse and axial directions. This quantity is the proportional deformation of a material under an applied stress.
ANSWER: strain [accept axial strain or transverse strain]
<Physics>
Summary
| 2024 ACF Regionals @ Berkeley | 01/27/2024 | Y | 1 | 10.00 | 100% | 0% | 0% |
| 2024 ACF Regionals @ JMU | 01/27/2024 | Y | 1 | 10.00 | 100% | 0% | 0% |
| 2024 ACF Regionals @ JMU | 01/27/2024 | Y | 1 | 10.00 | 100% | 0% | 0% |
| 2024 ACF Regionals @ Nebraska | 01/27/2024 | Y | 6 | 6.67 | 50% | 17% | 0% |
| 2024 ACF Regionals @ Imperial | 01/27/2024 | Y | 8 | 10.00 | 75% | 25% | 0% |
| 2024 ACF Regionals @ Vanderbilt | 01/27/2024 | Y | 1 | 10.00 | 100% | 0% | 0% |
| 2024 ACF Regionals @ MIT | 01/27/2024 | Y | 3 | 0.00 | 0% | 0% | 0% |
Data
| Dartmouth A | Brown A | 0 | 0 | 0 | 0 |
| Brandeis B | Boston University | 0 | 0 | 0 | 0 |
| Brandeis B | Boston University | 0 | 0 | 0 | 0 |
| Brandeis B | Boston University | 0 | 0 | 0 | 0 |
| Brandeis B | Boston University | 0 | 0 | 0 | 0 |
| Brandeis B | Boston University | 0 | 0 | 0 | 0 |
| Brandeis B | Boston University | 0 | 0 | 0 | 0 |
| Brandeis B | Boston University | 0 | 0 | 0 | 0 |
| Brandeis B | Boston University | 0 | 0 | 0 | 0 |