## Physics for Scientists and Engineers: A Strategic Approach with Modern Physics (3rd Edition)

$x(t) = (8.0~cm)~cos(\pi~t+\pi)$
The general equation for the position of an object in SHM is: $x(t) = A~cos(2\pi~f~t+\phi_0)$ It is known that: A = 8.0 cm f = 0.5 Hz At $t = 0$, the object has its most negative position. This shows that the basic cos-curve is shifted an angle of $\pi$ to the left. Therefore, $\phi_0 = \pi$. We can write the function for this motion as: $x(t) = (8.0~cm)~cos[(2\pi)(0.5)~t+\pi]$ $x(t) = (8.0~cm)~cos(\pi~t+\pi)$