Superposition 1

.PS
include(pstricks.m4)

scale=25.4

cct_init

define(`termrad_',`sourcerad_/4')
define(`terminal',`circle rad termrad_')

dy=25
dx=25

O: (0,0)

move to O

Ia: source(up_ dy,I,);llabel(,i_a,);rlabel(,2\;\text{mA},)
line right dx
{ dot(at Here)
  R1: resistor(down_ to (Here.x,O.y));rlabel(,R_1,);llabel(,10\;\text{k}\Omega,)
  dot(at Here)
}
line right dx*0.75
{ dot(at Here)
  line up dy
  Vx: source(right_ dx*1.25,V,,R);llabel(,v_x,);rlabel(,10\;\text{V},)
  line down to (Here.x,R1.start.y)
  dot(at Here)}
line right dx*0.25
{ dot(at Here)
  line down dy/10 chop 0 chop termrad_
  terminal
  R2: resistor(down_ dy*8/10 from last circle .c chop termrad_ chop termrad_);rlabel(,R_L,);llabel(,10\;\text{k}\Omega,);b_current(i_L,,O,E)
  terminal
  line down dy/10 from last circle .c chop termrad_ chop 0
  dot(at Here)
}
R3: resistor(right_ dx);rlabel(,R_3,);llabel(,20\;\text{k}\Omega,)
Ib: source(down_ to (Here.x,O.y),I,,R);rlabel(,i_{b},);llabel(,1\;\text{mA},)
line to O

.PE