Question

The image of an object formed by a mirror is real, inverted and its magnification is -1. If
the image is at the distance of 30cm from the mirror, where is the object placed? Find the
position of the image if the object is now moved 20cm towards the mirror. What is the
nature of the image obtained? Justify your answer with help of a ray diagram.​

Answer 1

For answer see the attachment.

Hope it helps ..

Answer 2

Answer:

+ 30 cm

Explanation:

Given :

Magnification = - 1

Image distance = 30 cm

We know

m = - v / u

- 1 = 30 / u

u = - 30 cm

Now we have ,

1 / f = 1 / v + 1 / u

1 /  f = 1 / - 30 - 1 / 30

f = - 15 cm

When object moved 20 cm

u' = - 30 + 20 = - 10 cm

We have f = - 15 cm

We have to find new image distance v'

Again ,

1 / f = 1 / v' + 1 / u'

- 1 / 15 = 1 / v' - 1 / 10

1 / v' = 1 / 30

v' = 30.

Nature of image as :

Virtual

Erect

Magnified.