- #1

kiwi101

- 26

- 0

For what value of is the final image of this two-lens system halfway between the two lenses?

My attempt:

I am working backwards:

s" = -9 (final virtual image displayed halfway between lenses)

f = 15

I solved for (1/s') + (1/s") = 1/f

s'= 5.6 cm (real image distance formed from lense 1)

f = 4cm

and now solve for s one more time and get s = 14

but that is wrong