Question

a concave lensee if focal length 15 cm is formed an image of distance 10 ​

Answer 1

Answer:

30cm

Explanation:

focal length (f)=15 cm

distance of image(v)=10cm

1/v+1/u=1/f

1/u=-(1/10)-(1-15)

1/u=-0.030

u=-30cm

so,the object is placed 30 cm away from concave lens