An Object Attached to a Coiled Spring Is Pulled Down $$\mathrm { a } = 5 ; \quad \mathrm { T } = 10 \text { seconds }$$

Multiple Choice

An object attached to a coiled spring is pulled down a distance a from its rest position and then released. Assuming that
the motion is simple harmonic with period T, write an equation that relates the displacement d of the object from its rest
position after t seconds. Also assume that the positive direction of the motion is up.
- $$\mathrm { a } = 5 ; \quad \mathrm { T } = 10 \text { seconds }$$

A) $d = 5 \cos ( 10 t )$
B) $d = - 5 \cos ( 10 t )$
C) $d = - 5 \cos \left( \frac { \pi } { 5 } t \right)$
D) $d = 5 \cos \left( \frac { \pi } { 5 } t \right)$