Period \((T)=2 \,s\)

\(\omega=\frac{2 \pi}{2}=\pi \,rad / s\)

When block just represent from a piston, maximum acceleration must be equal to \(g\).

\(g=-\omega^2 x\)

Acceleration is maximum when \(x=A\)

\(g=-\omega^2 A\)

or \(A=\frac{9.8}{\pi^2}\)

Maximum velocity \(=A \omega\)

\(=\frac{9.8}{\pi^2} \times \pi\)

\(=\frac{9.8}{\pi} \,m / s\)

\(=3.119 \,m / s =3.12 \,m / s\)