A converging lens of focal length 5cm is used as a magnifying glass by a man whose nearpoint is 35cm. Calculate the magnification given by the lens
A
8
B
7
C
6
D
5
E
4
Verified Correct Answer: C.
Physical Principles & Numerical Solution
\(\frac{1}{f} = \frac{1}{u} + \frac{1}{v}\)
= \(\frac{1}{5} - \frac{1}{35} = \frac{30}{175}\)
U = \(\frac{175}{30}\) = 5.8m
\(\frac{v}{u} = \frac{35}{5.8}\)
= 6
Source: Myschool Past Questions Archive (Record #33633)