34_Ch 23 College Physics ProblemCH23 Mirrors and Lenses -...

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CHAPTER 23
(b) When q , we find 3 = − f
( )
3
3
3 4
f f
f
p
f f
−
= =
− −
(c) In case (a),
4
3
4 3
q f
M
p f
= − = − = −
and in case (b),
3
4
3 4
q f
M
p f
−
= − = − = +
23.61 If R and , the focal length is given by
1
3.00 m = −
2
6.00 m R = −
1 1
2 2
1
1
.00 m 6.00 m
n n
n
 
   
− −
 
= − =
     

 
     
2
1 n 1 1
3.00 m 6
+
− f n
(
or
)
2
n
2 1
m
n n −
6.00
f = (1)
(a) If 1.5 n = and , then
1
0
2
1.00 n =
( )( )
6.00 m 1.00
12.0 m
1.00 1.50
f = = −
−
The thin lens equation gives
( )
( )
10.0 m 12.0 m
10.0 m 12.0 m