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

Options

A. If both A and R are true and R is the correct explanation of A.
B. If both A and R are true but R is not the correct explanation of A.
C. If A is true but R is false
D. If A is false but R is true.

Answer

A

Explanation

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.