Ladder

Gauss law — the ladder

2 distinct arguments against one idea, from the one that introduces it to the one that assumes the rest.
  1. +every line leaves: net flux counts the chargethe shape of the surface never enters the answer

    Counting what comes out, and never looking inside

    Draw any closed surface. The field crossing it depends only on the charge enclosed — not on where that charge sits, not on its shape, not on anything outside.

    rung 1 · electromagnetism
  2. 00.511.5-4-3-2-10log distancelog fieldpoint: slope −2measured -2.00line: slope −1measured -1.00plane: slope 0measured -0.00

    The shape decides the falloff, and the force law never changes

    A point charge gives an inverse square, a line gives an inverse, a plane gives a constant. All three come from the same law, and the exponent belongs to the geometry of the source rather than to the physics.

    rung 2 · electromagnetism

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