The Displacement D (In Meters) of an Object at Time $$d = - 1 \cos \left( \frac { \pi } { 2 } t \right)$$

Multiple Choice

The displacement d (in meters) of an object at time t (in seconds) is given. Describe the motion of the object. What is the
maximum displacement from its resting position, the time required for one oscillation, and the frequency?
- $$d = - 1 \cos \left( \frac { \pi } { 2 } t \right)$$

A) simple harmonic; $1 \mathrm {~m} ; \frac { 1 } { 4 } \mathrm { sec } ; 4$ oscillations/sec
B) simple harmonic; $- 1 \mathrm {~m} ; 4 \mathrm { sec } ; \frac { 1 } { 4 }$ oscillation/sec
C) simple harmonic; $1 \mathrm {~m} ; 2 \mathrm { sec } ; \frac { 1 } { 2 }$ oscillation/sec
D) simple harmonic; $1 \mathrm {~m} ; 4 \mathrm { sec } ; \frac { 1 } { 4 }$ oscillation/sec