5331 HW set 3
1. Jackson 7.20 2. Jackson 7.23 3. Wilcox 8.7.4 (a) and (b)
8.7.4 We briefly discussed the behavior of the dielectric
given approximately by (=l)
03 -I= (0)3 02
where op is the plasma frequency.
(a) Derive the explicit form of the response function, G(t), for this &(0). Find the group, Vg, and phase, Vp: velocities implied by this dielectric relation, and demonstrate that Vp > C > Vg
(b) In one dimension, show that the electric field (E(x,t) -;
u(x,t)) satisfies the modified wave equation,
22u - 1 22u + W3 dx2= c2 Dt2 + c2 u