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The resonant frequency of a circuit is f...

The resonant frequency of a circuit is f. If the capacitance is made 4 times the initial values, then the resonant frequency will become ……

A

`f/2`

B

2f

C

f

D

`4/f`

Text Solution

Verified by Experts

The correct Answer is:
A
`omega=1/sqrt(LC)`
In `2pif 1/sqrt(LC) 2pi` and L equal
`therefore f prop 1/sqrtC`
`therefore (f_2)/(f_1)=sqrt(C_1/C_2)=sqrt(C/(4C))=1/2`
`therefore f_2=f_1/2` but `f_1=f`
`therefore f_2=f/2`
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KUMAR PRAKASHAN-ALTERNATING CURRENTS -SECTION-D MCQs (DARPAN BASED ON TEXTBOOK)
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