# 3: Direct Current Circuits

- Page ID
- 21514

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- 3.1: Moving Charge
- We begin with some mathematical tools for dealing with moving charge, keeping in mind the observed physical law that charge is neither created nor destroyed.

- 3.2: Resistance and Energy Dissipation
- We now discard our assumption from electrostatics that conductors allow totally free (instantaneous) movement of electric charge, and take into account the effects of "electrical friction."

- 3.3: Networks of Batteries and Resistors
- We can employ analysis similar to what we used in static circuits to circuits that contain electric current passing through resistors, though it requires a twist to the notion of potential difference used in the static case.

- 3.4: Kirchhoff's Rules
- Not every conceivable circuit can be analyzed using the tools of the previous section. Here we learn some tools that can be used in more general cases.

- 3.5: RC Circuits
- Up to now, we have only considered the role of capacitors under static circumstances. We now incorporate them into our moving-charge networks.