Question

an object is placed at a distance of 30 cm from a concave lens produces an image at 60cm from the lens claculate the focal length​

Answer 1

Step-by-step explanation:

This is the correct answer for your question

Answer 2

Step-by-step explanation:

concave lens produces a virtual, erect diminished image.

Using Real Is Positive RIP Convention, u=30 and f=-15

1/u+1/v=1/f

1/30+1/v=−1/15

1/v=−1/15−1/30=−3/30=−1/10

v=−10M=v/u=−1/3

So image is erect, virtual, 1/3 size of object, and 10 cm from the lens, (between lens and object)