Question

least distance of distinct vision a) 15cm b) 25cm c)35cm d) 45cm​

Answer 1

Answer:

Given,

Focal length of convex lens, f=5cm

Position of image, v=25cm

Position of object, u=?

Apply lens formula

f

1

=

v

1

−

u

1

5

1

=

25

1

−

u

1

u=

4

25

cm

Magnifying power of instrument:

M=1+

f

D

M=1+

5

25

=6

Hence, object distance is

4

25

cm and magnifying power is 6

Answer 2

Answer:

b) 25 cm

is the least distance of distinct vision