Assertion (A) : LASER is used to measure distant object as moon. Reason (R) : They are highly coherent source of light.

Asked in mineral dev officier 2025 · Topic: Optics (Laser: Principles and applications)

1. (A) is true but (R) is false.
2. (A) is false but (R) is true.
3. Both (A) and (R) are true, and (R) is the correct explanation of (A).
4. Both (A) and (R) are true, but (R) is not the correct explanation of (A).

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