\(\mathrm I=\;\frac{\mathrm q}{\mathrm t}\)
\(\mathrm V=\frac{\mathrm W}{\mathrm q}\)
\(\mathrm R=\frac{\mathrm V}{\mathrm I}\)
\(\mathrm P=\frac{\mathrm W}{\mathrm t}=\mathrm V\mathrm I\)
Equivalent resistance for series components, \(\mathrm I=\;\) constant
\({\mathrm V}_\mathrm t={\mathrm V}_1+{\mathrm V}_2+..{\mathrm V}_\mathrm n\)
\({\mathrm R}_\mathrm t={\mathrm R}_1+{\mathrm R}_2+..{\mathrm R}_\mathrm n\)
Equivalent resistance for parallel components, \(\mathrm V=\) constant
\({\mathrm I}_\mathrm t={\mathrm I}_1+{\mathrm I}_2+..{\mathrm I}_\mathrm n\;\)
\(\frac1{{\mathrm R}_\mathrm t}=\frac1{{\mathrm R}_1}+\frac1{{\mathrm R}_2}+..\frac1{{\mathrm R}_\mathrm n}\)
\(\mathrm I=\;\) current, V_subscript_t= total potential difference, \({\mathrm V}_\mathrm n\) = the potential difference across each component, \({\mathrm R}_\mathrm t=\;\) equivalent resistance, \({\mathrm R}_\mathrm n\) = resistance of each component
\({\mathrm I}_\mathrm t={\mathrm I}_1+{\mathrm I}_2+..{\mathrm I}_\mathrm n\;\)
\(\mathrm V=\) potential difference, \({\mathrm I}_\mathrm t=\;\)= total current, \({\mathrm I}_\mathrm n\) = current in each of the components, \(\frac1{{\mathrm R}_\mathrm t}=\;\) the reciprocal of the equivalent resistance, \(\;\frac1{{\mathrm R}_\mathrm n}=\;\)= the reciprocal of the resistance of each component