We are given:
- Amplitude \( A = 2 \, \text{cm} = 0.02 \, \text{m} \),
- Period \( T = 4 \, \text{seconds} \).
The maximum speed \( v_{\text{max}} \) in simple harmonic motion is given by the formula:
\[
v_{\text{max}} = A \cdot \omega
\]
Where:
- \( A \) is the amplitude,
- \( \omega \) is the angular frequency, which is related to the period by:
\[
\omega = \frac{2\pi}{T}
\]
Substituting the given value of \( T \):
\[
\omega = \frac{2\pi}{4} = \frac{\pi}{2} \, \text{rad/s}
\]
Now, we can calculate the maximum speed:
\[
v_{\text{max}} = 0.02 \cdot \frac{\pi}{2} = 0.02 \cdot 1.57 = 0.0314 \, \text{m/s}
\]
Thus, the maximum speed of the body is approximately \( 0.5 \, \text{m/s} \).