The radius of circle, the period of revolution, initial position and sense of revolution are indicated in the figure.

y-projection of the radius vector of rotating particle P is

• A

  $\mathrm{y}\left(\mathrm{t}\right) = 3\cos \left(\frac{\mathrm{\pi t}}{2}\right), \mathrm{where} \mathrm{y} \mathrm{in} \mathrm{m}$

• B

  $y\left(t\right) = -3\cos 2\mathrm{\pi } \mathrm{t}, \mathrm{where} \mathrm{y} \mathrm{in} \mathrm{m}$

• C

  $\mathrm{y}\left(\mathrm{t}\right) = 4\sin \left(\frac{\mathrm{\pi t}}{2}\right), \mathrm{where} \mathrm{y} \mathrm{in} \mathrm{m}$

• D

  $\mathrm{y}\left(\mathrm{t}\right) = 3\cos \left(\frac{3\mathrm{\pi t}}{2}\right), \mathrm{where} \mathrm{y} \mathrm{in} \mathrm{m}$