The maximum acceleration experienced by a body undergoing simple harmonic motion is
\[a_{MAX} = \omega^2 A\]
where \[A , \: \omega\]
are the amplitude and the angular frequency of the motion.Suppose a body of mass 0.3 kg executes simple harmonic motion with amplitude
\[A=2.1 m\]
and
frequency \[f=20 Hz\]
.Then
\[\omega = 2 \pi f = 2 \pi \times 20 =40 \pi\]
.Then
\[a_{MAX} = \omega^2 A = (40 \pi)^2 \times 2.1=33161 m/s^2\]
Now use Newtons Second Law
\[F=ma\]
.The maximum force is
\[F_{MAX} =0.3 \times 33162=9948.6 N\]
.