Physics / advanced
Charged particles and collective plasma motion
Develop plasma scales, single-particle drifts, fluid descriptions, and magnetohydrodynamic waves with their ordering assumptions made explicit.
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Module 01 advanced
Charged particles and collective plasma motion
Develop plasma scales, single-particle drifts, fluid descriptions, and magnetohydrodynamic waves with their ordering assumptions made explicit.
- 01
Debye shielding and the plasma parameter
Derive the screening length and separate weak coupling, quasineutrality, and response-time assumptions.
32 min - 02
The electron plasma oscillation frequency
Derive the restoring field of displaced electrons and distinguish angular frequency, oscillation period, and thermal corrections.
31 min - 03
Cyclotron motion and magnetic moment
Track signed gyromotion, perpendicular energy, and the assumptions behind a magnetic adiabatic invariant.
33 min - 04
Guiding-centre electric and gradient drifts
Derive common electric drift and charge-dependent magnetic drift with explicit vector directions and ordering.
34 min - 05
Magnetic mirrors and loss cones
Use energy and magnetic-moment conservation to derive reflection conditions and the correct velocity-space loss fraction.
34 min - 06
Two-fluid plasma equations
Take species moments, identify the closure problem, and connect small velocity differences to measurable current.
35 min - 07
The ordering behind ideal magnetohydrodynamics
Reduce species dynamics to a conducting bulk fluid and test the scale assumptions behind the ideal induction equation.
36 min - 08
Alfvén and magnetosonic waves
Resolve magnetic tension and compression into three ideal MHD branches with explicit propagation-angle dependence.
36 min - 09
Magnetohydrodynamic equilibria
Balance pressure against magnetic pressure and tension, calculate a slab current, and separate equilibrium from stability.
35 min - 10
Magnetic reconnection and frozen-flux limits
Derive the material-loop flux constraint, identify its nonideal failure, and calculate a conditional Sweet–Parker estimate.
38 min