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A simple spring mass vibrating system has a natural frequency of fn. If the spring stiffness is halved and mass is double, then the natural frequency will become

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ISRO MCF Technical Assistant Mechanical 23 June 2019 Official Paper
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  1. fn/2
  2. 2fn
  3. 4fn
  4. 8fn

Answer (Detailed Solution Below)

Option 1 : fn/2
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Detailed Solution

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Explanation:

The natural frequency of a spring-mass system is given by,

   and  

where k = spring stiffness and m = mass 

If spring stiffness is halved and mass is doubled

then the natural frequency is given by

Hence, the natural frequency will become half.

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