MCQ
Assertion: Two convex lenses joined together cannot produce an achromatic combination.

Reason : The condition for achromatism is $\frac{{{\omega _1}}}{{{f_1}}} + \frac{{{\omega _2}}}{{{f_2}}} = 0$ where symbols have their usual meaning.

  • If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
  • B
    If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.
  • C
    If the Assertion is correct but Reason is incorrect.
  • D
    If both the Assertion and Reason are incorrect.

Answer

Correct option: A.
If both Assertion and Reason are correct and the Reason is a correct explanation of the Assertion.
a

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