Q. The displacement of a damped harmonic oscillator is given by $x\left(t\right)=e^{- 0 . 1 t}cos\left(10 \pi t + \varphi\right)$ , 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
NTA AbhyasNTA Abhyas 2022
Solution: