Question

What's the answer to 1/3rd magnification and concave lens of 20 cm focal length, find object distance? (Science Board Exam)​

Answer 1

I got -80

M= -1/3

v/u=-1/3

U=-3v

F=20cm

F=uv/u-v

20=-3v²/-4v

-80=3v

V=80/3

U=-3v

U=-3x80/3

U= -80cm

Plz mark as brainliest....

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