The equation of motion for simple harmonic motion (SHM) is given by:
\[
y = A \sin(\omega t) + B \cos(\omega t)
\]
The amplitude of the motion is given by:
\[
\text{Amplitude} = \sqrt{A^2 + B^2}
\]
Here, \( A = 1 \) and \( B = 1 \) in the equation \( y = \sin(\omega t) + \cos(\omega t) \).
Therefore, the amplitude is:
\[
\text{Amplitude} = \sqrt{(1)^2 + (1)^2} = \sqrt{2}
\]
Thus, the amplitude is \( \sqrt{2} \).