3
3
3
1
1
1
v
u
f
−
=
or
  
3
1
1
1
30
v =
+
∞
or
v3 = 30 cm
The final image is formed 30 cm to the right of the third lens 9 6  REFRACTION THROUGH A PRISM
Figure 9 21 shows the passage of light through
a triangular prism ABC