Solved UPSC CDS/OTA Question
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Q · Modern PhysicsMedium · 45s
Laser vs Torchlight Intensity A laser beam of 0.2 W can drill metal, but a 1000 W torchlight cannot because:
TopicModern Physics
Question Typemultiple choice
DifficultyMedium
Marking+1 / −0.33
Test Duration30 min
Step-by-Step Solution
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The laser's coherence and ability to concentrate energy into a tiny spot gives it much higher intensity than a broad, unfocused 1000‑W torchlight, despite lower power.
Final Answer: Option B - Laser is coherent, monochromatic and focused