A mirror forms image 30 cm from mirror for object at 60 cm. Find focal length.

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Given: Object distance u = 60 cm Image distance v = 30 cm Mirror formula: 1/f = 1/u + 1/v 1/f = 1/60 + 1/30 1/f = (1 + 2)/60 1/f = 3/60 1/f = 1/20 f = 20 cm Answer: 20 cm

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Asked 34 days ago|2/1/2026 10:44:00 AM

Updated 33 days ago|2/2/2026 5:49:57 AM

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cruz30

Given:
Object distance u = 60 cm
Image distance v = 30 cm
Mirror formula:
1/f = 1/u + 1/v
1/f = 1/60 + 1/30
1/f = (1 + 2)/60
1/f = 3/60
1/f = 1/20
f = 20 cm
Answer: 20 cm

Added 33 days ago|2/2/2026 5:48:07 AM

This answer has been confirmed as correct and helpful.

Salas1987

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Added 33 days ago|2/2/2026 5:49:57 AM

Deleted by Salas1987 [2/2/2026 5:50:04 AM]

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cruz30

Given:
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Added 33 days ago|2/2/2026 6:04:01 AM

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