Convex Lens Object-Image Distance – Rankers Physics

Refraction by Plane Surfaces: Practice Problem & Solution

Assertion (A): Minimum distance between a real object and its real image formed by a convex lens is three times the focal length of lens. Reason (R): Distance between an object and its real image formed by convex lens is minimum when magnification produced by the lens has minimum value.  
Both (A) & (R) are true and the (R) is the correct explanation of the (A)
Both (A) & (R) are true but the (R) is not the correct explanation of the (A)
(A) is true but (R) is false
Both (A) and (R) are false

Solution Explained:

To solve this problem, we apply the core principles of Refraction by Plane Surfaces. Understanding the underlying formula is key to arriving at the correct answer below:

For a convex lens, the minimum distance between a real object and its real image is \(4f\), occurring when the object is placed at \(2f\). At this point, the magnification is \(|m|=1\). The minimum magnitude of magnification approaches zero as the object moves to infinity. Hence, both Assertion (A) and Reason (R) are false.

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Similar Practice Questions

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