Thread: Thin Lenses
View Single Post
Sep15-05, 02:54 AM
P: n/a
An eraser of height 1.0cm is placed in front of a two-lens system. Lens 1(nearer the eraser) has focal length f1=-15cm, lens 2 has f2=12cm, and the lens seperation is d=12cm. For the image produced by lens 2, what is the image distance i2?

What I did is setup some equations.

For lens 1: 1/-15 = 1/P1 + 1/i1 and m1 = -i1/P1
For lens 2: 1/12 = 1/(i1+12) + 1/i2 and m2= -i2/(i1+12)

I'm having trouble solving this. I can't get past having one more unknown than equation. Any help will be appretiated, thanks.
Phys.Org News Partner Science news on
Hoverbike drone project for air transport takes off
Earlier Stone Age artifacts found in Northern Cape of South Africa
Study reveals new characteristics of complex oxide surfaces