A forced oscillator is acted upon by a force, `F=F_(0)sinomegat`. The amplitude of the oscillator is given by `A=(55)/(sqrt((2omega^(2)-36omega+9)))`
What is the resonance angular freuqnecy (in rad/s)?

Options

A. 36
B. 18
C. 9
D. 2

Answer

C

Explanation

Given, `A=(55)/(sqrt((2omega^(2)-36omega+9)))`
At resonance, the apmplitude is maximum. This is possible
if `sqrt(2omega^(2)-36omega+9)` is minimum.
For, this, `(d)/(domega)[2omega^(2)-36omega+9]` must be=0
`therefore4omega-36=0` or `omega=9`