A wheel is spinning at 44 with its axis vertical. After 15 , it's spinning at 60 with its axis horizontal. Find (a) the magnitude of its average angular acceleration and (b) the angle the average angular acceleration vector makes with the horizontal. Just trying to work out what I'm doing wrong here to find the average angular acceleration. I used angular acceleration = final velocity - initial velocity all divided by the time pasted. (Also converted units from rpm to rad/s2 by multiplying by (2∏/60) So far my initial answer is 0.11 rad/s2 which is apparently wrong, any idea what I can be doing wrong here?