An object at a distance of 30 cm from a concave mirror gets its image at the same point. The focal length of the mirror is

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An object at a distance of 30 cm from a concave mirror gets its image at the same point. The focal length of the mirror is

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(a) – 30 cm
(b) 30 cm
(c) – 15 cm
(d) +15 cm

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Class 10 science Rohit QNA 3 years 2021-11-19T17:00:50+00:00 2021-11-19T17:00:50+00:00 1 Answer 13 views Enlightened 0

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Rohit QNA Enlightened · Answer 1 · 2021-11-19T17:01:10+00:00

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2021-11-19T17:01:10+00:00 November 19, 2021 at 5:01 pm

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Answer: c
Explanation:
(c) When object is placed at 2F, the
image formed by concave mirror is
also at 2F.
So 2F = -30 or F = -15 cm

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An object at a distance of 30 cm from a concave mirror gets its image at the same point. The focal length of the mirror is

An object at a distance of 30 cm from a concave mirror gets its image at the same point. The focal length of the mirror is

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