Physics-
General
Easy

Question

Assertion : A laser beam 0.2 W power can drill holes through a metal sheet, whereas 1000 W torch-light cannot.
Reason : The frequency of laser light is much higher then that of torch light.

  1. If both assertion and reason are true and the reason is the correct explanation of the assertion.    
  2. If both assertion and reason are true but reason is not the correct explanation of the assertion.    
  3. If the assertion and reason both are false.    
  4. If assertion is false but reason is true.    

hintHint:

A laser beam is a beam of light which is light amplification by stimulated emission of radiation.

The correct answer is: If the assertion and reason both are false.


    A laser beam is a beam of light which is light amplification by stimulated emission of radiation.
    The energy per unit area of the laser beam is very high as compared to the torch light.

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