Lens Behavior in Different Media – Rankers Physics

Lens Makers Formula/ Len's Formula: Practice Problem & Solution

Assertion (A): A convex lens of glass \(\mu = 1.5\) behave as a diverging lens when immersed in carbon disulphide of higher refractive index \(\mu = 1.65\). Reason (R): A diverging lens is thinner in the middle and thicker at the edges.  
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 Lens Makers Formula/ Len's Formula. Understanding the underlying formula is key to arriving at the correct answer below:

Assertion (A) is true; a lens acts as a diverging lens if the surrounding medium's refractive index is greater than the lens material's. Reason (R) is true; a concave lens (a common diverging lens) has this shape. R describes the shape of a diverging lens, not why a convex lens changes its behavior in a different medium. Thus, both are true, but R does not explain A.

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