Answer
(a) $728.29~rev/min$
(b) $4,576~rad/min$
Work Step by Step
(a) $$v_t=65~\frac{mi}{hr}\times\frac{5,280~ft}{1~mi}\times\frac{1~hr}{60~min}=5,720~ft/hr$$
$$r=\frac{D}{2}=\frac{2.5}{2}=1.25~ft$$
$$n=\frac{v_t}{2\pi(r)}=\frac{5,720}{2\pi(1.25)}=728.29~rev/min$$
(b) $$\omega=2\pi n=2\pi(728.29)=4,576~rad/min$$
