Question

In case of damped oscillation the frequency of oscillation is

• A. greater than natural frequency
• B. less than natural frequency
• C. equal to natural frequency
• D. both $\left(a\right)$ and $\left(b\right)$

Answer 1

The correct option is B less than natural frequency

Angular frequency of damped oscillation
${\omega }^{\prime }=\sqrt{{\omega }_0^2-{\left(\frac{b}{2m}\right)}^2}$
$\Rightarrow {\omega }^{\prime }<{\omega }_0$
Where natural angular frequency ${\omega }_0=\sqrt{\frac{k}{m}}$
Since frequency and angular frequency are related as,
$\omega =2\pi f$
Hence, frequency of damped oscillation is less than natural frequency.