A particle of mass $m$ describes a circle of radius $r$. The centripetal acceleration of the particle is $\frac{4}{r^2}$. The momentum of the particle :

A particle moving along a circular path. The angular velocity, linear velocity, angular acceleration and centripetal acceleration of the particle at any instant respectively are $\overrightarrow{\omega }, \overrightarrow{v}, \overrightarrow{\alpha }, {\overrightarrow{a}}_c$ . Which of the following relation is/are correct : 
(a) $\overrightarrow{\omega }\perp \overrightarrow{\mathrm{v}}$    

(b) $\overrightarrow{\omega }\perp \overrightarrow{\mathrm{\alpha }}$

(c) ${\overrightarrow{a}}_c\perp \overrightarrow{\omega }$

(d) $\overrightarrow{\omega }\perp {\overrightarrow{a}}_c$