Physics - SHM Question with Solution | TestHub

The displacement of a damped harmonic oscillator is given by$x\left(t\right)={\mathrm{e}}^{-0.1t} \cos \left(10\mathrm{\pi }t+\phi \right)$, where$t$is the time in seconds. The time taken for the amplitude of the oscillator to drop to half of its initial value is close to