Consider the compound optical system shown in the diagram, where two thin lenses
ID: 1516146 • Letter: C
Question
Consider the compound optical system shown in the diagram, where two thin lenses of focal lengths 9.5 cm (left lens) and 1.5 cm (right lens) are separated by a distance 44 cm.
(a) If an object is placed a distance do = 17.7 cm to the left of the first lens (the left one) as shown in the figure, how far to the right of that lens, in centimeters, is the image formed?
(b) What is the magnification of the first lens?
(c) What is the object distance, in centimeters, for the second lens (the right lens)?
(d) What is the image distance, in centimeters, for the second lens?
(e) What is the magnification of the second lens?
Explanation / Answer
(a)
for left lens
do = 17.7 cm
di = ?
fL = 9.5 cm
1/d0 + 1/di = 1/fL
1/17.7 + 1/di = 1/9.5
di = 20.5 cm <<<--------asnwer
_++++++++++++++
(b)
m = -di/do = -20.5/17.7 = -1.16
_____________
(c)
for right lens
d0 = 44-20.5 = 23.5 cm
++++++++
(d)
1/do + 1/di + 1/fR
1/23.5 + 1/di = 1/1.5
di = 1.6 cm
++++++++++++
(e)
m = -di/do = 1.6/23.5 = -0.06