f−f0eV V0\frac{\mathrm{f}-\mathrm{f}_{0}}{\mathrm{eV} \mathrm{~V}_{0}}eV V0f−f0
f0−fe0\frac{f_{0}-f}{e_{0}}e0f0−f
eV0f−f0\frac{\mathrm{eV}_{0}}{\mathrm{f}-\mathrm{f}_{0}}f−f0eV0
V0e(f−f0)\frac{V_{0}}{e}\left(f-f_{0}\right)eV0(f−f0)