The blades of a ceiling fan have a radius of 0.378 m and are rotating about a fixed axis with an angular velocity of +1.44 rad/s. When the switch on the fan is turned to a higher speed, the blades acquire an angular acceleration of 2.12 rad/s2. After 0.485 s have elapsed since the switch was reset, what are the:
(a) the total acceleration (in m/s2) of a point on the tip of a blade m/s2; and
(b) the angle ϕ between the total acceleration and the centripetal acceleration ac?
