AP EAMCET Engineering 2018 Apr 24 Shift 1 Paper

From the expression of the magnifying power,
m=

f0

fe

10=

f0

fe

f0=10fe...... (I)
The length of tube is,
f0+fe=110...... (II)
From equation (I) and (II),
10fe+fe=110
fe=10cm
f0=100cm
The expression of magnifying power, when image is formed at near point is,
m=

f0

fe

(1+

fe

D

)
Substitute values,
m=

100

10

(1+

10

25

)
m=10×

35

25

m=14