Question
Download Solution PDFA beam of light after passing through a concave lens appears to diverge from a point 25 cm behind the lens. The power of the lens is
Answer (Detailed Solution Below)
Detailed Solution
Download Solution PDFThe correct answer is - 4 D.
Key Points
- A beam of light after passing through a concave lens appears to diverge from a point 25 cm behind the lens then power of the lens is -4 D
- If the focal length is specified in metres, the lens's power is calculated in diopters (D).
- A diverging lens has a negative optical power, whereas a converging lens has a positive optical power.
Additional Information
- When a parallel beam is incident on a concave lens after refraction through the lens, it seems to deviate from the lens's focus.
- Consequently, the lens's focal length is 25 cm and the focal length of a concave lens is negative by sign convention.
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