- #1
MaysMrDolphin
- 2
- 0
Homework Statement
. Three thin lenses, each with a focal length of 40.0 cm, are aligned on a common axis; adjacent lenses are separated by 52.0 cm. Find the position of the image of a small object on the axis, 80.0 cm to the left of the first lens.
d=52cm between
f=40cm
d of object=80cm
Homework Equations
1/f=1/di+1/do
The Attempt at a Solution
[/B]
by the equation:
1/40cm = 1/80cm + 1/di (1st lens)
di= 80cm
52-80cm= -28cm
2nd lens
1/40 = -1/28 + 1/di
di (lens 2) = 16.47
52-16.47= 35.53cm
3rd lens
1/40 = 1/35.33+1/di
di=-302.6 ---> This is where I'm stuck, the answer is supposed to be 134 cm to the left according to the book. Even if I add 104 cm to the answer, it still doesn't come close enough. Any thoughts on this?
Last edited by a moderator: