OpenStax University Physics/E&M/Capacitance

(Vol. 2):    5:Electric Charges and Fields    6:Gauss's Law    7:Electric Potential    8:Capacitance    9:Current and Resistance    10:Direct-Current Circuits    11:Magnetic Forces and Fields    12:Sources of Magnetic Fields    13:Electromagnetic Induction    14:Inductance    15:Alternating-Current Circuits    16:Electromagnetic Waves


Chapter 8 edit

Capacitance edit

  defines capacitance. For a parallel plate capacitor,   where A is area and d is gap length.

▭   and   for a spherical and cylindrical capacitor, respectively
▭ For capacitors in series (parallel)  
▭    ▭ Stored energy density  
▭ A dielectric with   will decrease the capacitor's electric field   and stored energy  , but increase the capacitance   due to the induced electric field  

For quiz at QB/d_cp2.8 edit

  defines capacitance.

  where A is area and d<<A1/2 is gap length of parallel plate capacitor


  = stored energy

  = energy density