Discuss "what will happen if the motion of the Earth around the Sun is not a periodic motion'.

The displacement of a simple harmonic motion is given by $y\left(t\right)=A \sin (\omega t+\phi )$ where $A$ is amplitude of the oscillation, ($\omega$ is the angular frequency and $\phi$ is the phase. Let the amplitude of the oscillation be $8 \mathrm{cm}$ and the time period of the oscillation is $24 \mathrm{s}$. If the displacement at initial time $(\mathrm{t}=0 \mathrm{s})$ is $4 \mathrm{cm}$, then the displacement at $t=6 \mathrm{s}$ is