We have a convex lens with a focal length of 8cm, which is 12cm from the second converging lens that has a focal length of 4cm. An object is 12cm from the first lens. Where is the final image?
1/do + 1/di = 1/f
The Attempt at a Solution
So i know I have to apply the lens equation to both lens, starting with the first lens:
1/di = 1/f - 1/do = 1/8cm + 1/12cm = 1/24cm
here is where I get confused. Applying the lens equation to the second lens
1/di2= 1/f - 1/do(do here equals di1)
1/di2= 1/4cm - 1/12cm = 2/12cm
di1 + di2 = 30cm
The answer is 27cm, I've checked my math several times and still get the incorrect answer.
any help is greatly appreciated.