Question

69. A concave lens has focal length of 15 cm. At whatdistance should the object from the
lens be placed so that it forms an.image at 10 cm from the lens? Also, the
magnification produced by the lens en
30cm, +0.33
B. 30mmy +0.33
C 30cm,-0.33
D. 30mm, -0.33​

Answer 1

Answer:

Hey

Explanation:

f = -15 cm

v = -10 cm

Lens formula : 1/v – 1/u =1/f

1/-10 – 1/u = 1/-15

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

1/u = -1/30

u = -1/30

u = -30 cm

Object should be placed at a distance of 60 cm on the left side of the lens.

m = v/u = -10/-30 = + 0.33