Question

Assertion (A): A convex lens, when immersed in a liquid, disappears.
Reason (R): The refractive indices of the material of the lens and the liquid are equal.

• A. Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
• B. Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
• C. Assertion (A) is true, but Reason (R) is false.
• D. Assertion (A) is false and Reason (R) is also false.

Hint:

When studying optics, it's essential to understand how the refractive index affects light transmission and bending at interfaces. Similar refractive indices can make objects visually disappear in mediums.

Answer 1

The Correct Option is A

This question examines the disappearance of a convex lens when submerged in a liquid, drawing upon principles of light refraction and media interaction.

Assertion (A): A convex lens becomes invisible when placed in a specific liquid.

Reason (R): The refractive indices of the lens material and the surrounding liquid are identical.

The relationship between the assertion and reason is rooted in the concept of refractive index. Details are as follows:

• Refractive Index: This property quantifies how light bends when transitioning between media. The lens is visible in air due to the disparity in refractive indices between the lens and air, causing light to refract.
• Immersion in Liquid: When the lens and the liquid share the same refractive index, light does not bend upon entering the lens. This absence of refraction renders the lens invisible.

Conclusion: Both the assertion and the reason are accurate. A convex lens becomes invisible in a liquid if their refractive indices match, validating that the reason correctly explains the assertion.

Correct Option: Both Assertion (A) and Reason (R) are true, and Reason (R) provides a correct explanation for Assertion (A).