Question

ol Path of integration of pro Ga wh (Eq URE 30-6. A cross section through a spherical or a cylin- drical capacitor. The electric hield at any point P in the interior is whe due only to the inner conductor. The path of integration for evalu ing Eq. 30-7 or Eq. 30-10 is shown. 30-2

question 27

Answer 1

Consider a cylinder with concentric radius a<r<b Let "q" be the charge on the inner surface of cylinder The electric field at a point of distance "r" from cylinder axis is, The energy density at that point is, The energy in the cylinder over volume is, (2t)dr In But the energy stored in full cylinder is, In Since, 2 a) 247EL a 1/2