MCQ
Laser beams are used to measure long distances because
- AThey are monochromatic
- BThey are highly polarised
- CThey are coherent
- ✓They have high degree of parallelism
✓
Answer
Correct option: D.
They have high degree of parallelism
d
(d) Laser beams are perfectly parallel. So that they are very narrow and can travel a long distance without spreading. This is the feature of laser while they are monochromatic and coherent these are characteristics only.
(d) Laser beams are perfectly parallel. So that they are very narrow and can travel a long distance without spreading. This is the feature of laser while they are monochromatic and coherent these are characteristics only.
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