Question
Magnetic field lines in these substances are governed by the “frozen-in flux” theorem. For 10 points each:
[10e] Name these substances that are modeled as a perfectly conducting fluid in magnetohydrodynamics. At high temperatures, gases ionize into this state of matter.
ANSWER: plasmas
[10h] In MHD, this quantity can be written as a sum of tension and pressure terms, the former of which is proportional to the curvature of field lines. Classically, this quantity per unit volume is equal to “J cross B.”
ANSWER: magnetic force [accept magnetic force density; prompt on force or Lorentz force]
[10m] Alfvén (“all-VANE”) waves, which result from tension on magnetic field lines, were theorized to cause the anomalously high temperature of this region. “Loops” of magnetic flux in this region can cause CMEs.
ANSWER: corona [prompt on the Sun]
<Physics>
Summary
| 2023 ACF Winter @ Columbia | 11/11/2023 | Y | 8 | 20.00 | 100% | 100% | 0% |
Data
| Columbia A | Penn B | 10 | 0 | 10 | 20 |
| Cornell C | Haverford | 10 | 0 | 10 | 20 |
| Princeton A | NYU B | 10 | 0 | 10 | 20 |
| Yale A | Penn A | 10 | 0 | 10 | 20 |
| Princeton B | Vassar | 10 | 0 | 10 | 20 |
| Rutgers A | Rowan A | 10 | 0 | 10 | 20 |
| Yale B | NYU A | 10 | 0 | 10 | 20 |
| Yale C | Rutgers B | 10 | 0 | 10 | 20 |