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NEET2001PhysicsWave OpticsActual

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

Options

  1. AIf both A and and Reason are true and Reason is the correct explanation of Assertion.
  2. BIf both Assertion and Reason are true but Reason is not the correct explanation of Assertion.
  3. CIf Assertion is true but Reason is false.
  4. DIf Assertion is false but Reason is true.

Correct answer

A. If both A and and Reason are true and Reason is the correct explanation of Assertion.

Step-by-step solution

As LASER is highly monochromatic and highly coherent, we can send a LASER beam to the moon, from where it comes back reflected without much loss of intensity. That's why the large distances can be measured accurately with the help of LASER.

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