\(\def \u#1{\,\mathrm{#1}}\)
\(\def \abs#1{\left|#1\right|}\)
\(\def \ast{*}\)
\(\def \deg{^{\circ}}\)
\(\def \ten#1{\times 10^{#1}}\)
\(\def \redcancel#1{{\color{red}\cancel{#1}}}\)
\(\def \BLUE#1{{\color{blue} #1}}\)
\(\def \RED#1{{\color{red} #1}}\)
\(\def \PURPLE#1{{\color{purple} #1}}\)
\(\def \th#1,#2{#1,\!#2}\)
\(\def \lshift#1#2{\underset{\Leftarrow\atop{#2}}#1}}\)
\(\def \rshift#1#2{\underset{\Rightarrow\atop{#2}}#1}}\)
\(\def \dotspot{{\color{lightgray}{\circ}}}\)
How Things Move
Why Things Move
current
amperes
conventional current
- Current (\(I\)) measured in A
In a steady current, the total current into an object is equal to the total current out of it.
In a wire, current moves towards lower potential.
"Current flows downhill."
batteries
emf
schematic symbol
power supplies
resistance
resistors
ohm's law
\(R={\Delta V\over I}\)
terminals
equivalent resistance
series
parallel
\(R_{eq} = {\Delta V\over I}\)
\(R_{eq} = R_1 + R_2 + \dots\)
for resistors in series
\(\frac1{R_{eq}} = \frac1{R_1} + \frac1{R_2} + \dots\)
(for resistors in parallel)