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.
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.
Reason (R): The refractive indices of the material of the lens and the liquid are equal.
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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.
Updated On: Feb 19, 2025
- Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
- Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
- Assertion (A) is true, but Reason (R) is false.
- Assertion (A) is false and Reason (R) is also false.
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The Correct Option is A
Solution and Explanation
Analysis of Assertion (A):
The assertion is true. A convex lens can indeed seem to disappear when immersed in a liquid if the refractive indices of the lens and the liquid are the same, because there is no change in the speed of light at the boundary.
Analysis of Reason (R):
The reason is true and provides the correct explanation for the assertion. If the refractive indices of the lens and the liquid are equal, light does not bend at the interface, making the lens invisible in the liquid.
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