Physics-
General
Easy
Question
Time period of a block suspended from the upper plate of a parallel plate capacitor by a spring of stiffness 
is 
When block is uncharged. If a charge 
is given to the block then, the new time period of oscillation will be
The correct answer is:
The forces that act on the block are 
and 
Since and 
are constant forces, the only variable elastic force changes by 
Where 
is the elongation in the spring 
unbalanced (restoring) force 
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