Question

60. If power of the eyepiece (L2) is 5 diopters and it forms an image at a distan of 80 cm from its optical centre, at what distance should the object be? a) 12 cm (b) 16 cm 18 cm (c) 20 cm (d)​

Answer 1

Step-by-step explanation:

Given magnification m=−1 and object distance u=−20cm

We know magnification m=

u

−v

v=−mu=(−1)(−20)=20cm

Now from lens formula we have,

v

1

−

u

1

=

f

1

20

1

−

20

−1

=

f

1

f=10cm

Now powerp=

f

1

=

100

10

1