Persistence of Vision and Eye Anatomy – Rankers Physics

Refraction by Spherical Surfaces: Practice Problem & Solution

Assertion (A): The persistence of vision \(1/16\) second is used in cinematography. Reason (R): The human eye forms the real image of an object at its retina.  
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

Short Solution (Best for NEET):

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

Assertion (A) is true; the brain's retention of images for about \(1/16\) second creates motion from rapid stills. Reason (R) is true; the eye's lens system forms a real, inverted image on the retina. R describes a fundamental eye function, which is a prerequisite for A but not its direct explanation. Thus, both are true, but R does not explain A.

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