An object 30 cm high is placed perpendicular to the principal axis of a concave lens of focal length 7.5 cm. The image is formed at a distance of 5.0 cm from the lens. Calculate:

(i) Distance at which object is placed, and (ii) size and nature of image formed.

Asked by Topperlearning User | 21st Jul, 2017, 03:05: PM

Expert Answer:

Object height, h = 3.0 cm; Focal length, f = -7.5 cm

Image distance, v = -5.0 cm (image forms on the same side as the object in concave lens)

Lens formula: 
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The object is at 15 cm from the concave lens in the direction of incident ray.
Magnification,
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The image is virtual and erect, and its size is 1 cm.

Answered by  | 21st Jul, 2017, 05:05: PM

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