JEE Main Physics question

**Assertion:** Nowadays a standard metre is defined in terms of the wavelength of light. **Reason:** Light has no relation with length.

(A)Assertion is True, Reason is True; Reason is correct explanation for Assertion
(B)Assertion is True, Reason is True; Reason is not correct explanation for Assertion
(C)Assertion is True, Reason is FalseCorrect
(D)Assertion is False, Reason is True

Answer: (C)

Solution

The metre has historically been defined via the wavelength of light (and is now tied to the speed of light), so the Assertion is true.

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Question ID VK-157511