Homework Help: Physics: Focal length why is my answer wrong?

Posted by Sar on Thursday, October 28, 2010 at 5:55pm.

An old refracting telescope in a museum is 44.0 cm long and the caption states that the telescope magnifies images by a factor of 29.0. Assuming these numbers are for viewing an object an infinite distance away with minimum eyestrain, what is the focal length of each of the two lenses?
cm (objective)
cm (eyepiece)

For this I have done fo/fe = 29 and fo+fe = 44
29fe = 44
fe=1.6
then
(29)(1.6) = 46.4
But both these answers are wrong. Why? I cannot figure this out for the life of me. Please help.

Physics: Focal length why is my answer wrong? - MathMate, Thursday, October 28, 2010 at 6:20pm
if fo/fe = 29 and fo+fe = 44
then
fo=29fe
fo+fe=29fe+fe=30fe=44
fe=1.47
fo=44-fe=42.53
Physics: Focal length why is my answer wrong? - Sar, Thursday, October 28, 2010 at 6:54pm
Actually, those answers are incorrect.

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