Question
The nth term in this series includes a rank-n tensor with two-n-plus-one components. For 10 points each:
[10h] Name this mathematical series that is used to approximate the electrostatic potential at large distances from a charge distribution.
ANSWER: multipole expansion
[10e] The monopole term in the multipole expansion is given by this law. A Frenchman names this inverse-square law that is central to electrostatics.
ANSWER: Coulomb's law
[10m] Higher-order terms of the multipole expansion feature Legendre polynomials evaluated at this function of the quantity alpha, which relates the vectors r and r-prime. Via Taylor expansion, this function is often approximated as "one minus x-squared-over-two."
ANSWER: cosine
<Science - Physics>
Data
Summary
| Tournament | Edition | Exact Match? | Heard | PPB | Easy % | Medium % | Hard % |
|---|---|---|---|---|---|---|---|
| 2025 PACE NSC | 06/07/2025 | Y | 42 | 11.90 | 81% | 38% | 0% |