Question

an object is placed at 20cm away from the concave mirror whose focal length is 10cm find the image distance ​

Answer 1

Answer:

20 cm away the mirror

Explanation:

Because Focal length = 10 cm(Given)

•°•Centre of curvature = 2×10 = 20 cm = Position of the object

We know that if an object is placed in the centre of curvature, then the image will be formed in the centre of curvature only. Thus, the image is formed at 20 cm away from the mirror.

Answer 2

Answer:

distance of object from a mirror is = -20cm

and a focal length is = -10 cm

use formula‐

1/v+1/u = 1/f

1/v = 1/f - 1/u

1/v = -1/10 - (-1/20)

1/v = -1/10 + 1/20 ( by taking LCM)

1/v = 1/20

v = 20 cm

here is ur answer..

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