Question

u v f

60 cm A cm 15 cm

B cm 15 cm 30 cm

60 cm 60 cm C cm

15 cm D cm 45 cm

write the values of A,B,C and D​

Answer 1

Answer:

Focal length (f ) = -15 cm

Distance of image (v) = -10 cm

\(\frac{1}{v} – \frac{1}{u} = \frac{1}{f}\)

1/u = -(1/10) – (1/- 15)

1/u =1/15 – 1/10

1/u = -0.033

u = -30 cm

So, the object is placed 30 cm away from the concave lens.