coulomb’s law is a principle that deals with the force that two charged particles exhibit to each other.

constituents

• \(k\), Coulomb’s Constant, found roughly to be \(9 \times 10^{9} \frac{N m^{2}}{C}\)
• \(q_{1,2}\), the charge of the two particles you are analyzing
• \(r\), distance between particles

requirements

\begin{equation} \vec{F_{E}} = k \frac{q_1q_2}{r^{2}} \end{equation}

additional information

interpreting signs on \(F_{e}\)

• negative: attraction force between changes (the points have opposite signed charges, and so attract)
• positive: repulsion force between changes (the point have the same signed change, so repel)

alternative formulation of Coulomb’s Law

The law is often redefined with the language of the premittivity of free space:

“if thing didn’t happen would I have…”

requires manipulating counterfactual information—not what the current known states are, but what are the next possible states.

Inside , there is already a few principles which are counterfactual.

1. Conservation of energy: a perpetual machine is *impossible
2. Second law: its impossible to convert all heat into useful work
3. Heisenberg’s uncertainty: its impossible to copy reliable all states of a qubit

With the impossibles, we can make the possible.

counting asks: “how many possible outcomes satisfy an event?” You create a “generative story” to think about how you can count for the total choices.

(like, 3 times will we roll even in a regular fair dice)

step rule of counting