Position of a point on a turning wheel..

[imatreyu]

Homework Statement

A wheel 60 cm in diameter rotates with a constant angular acceleration of 4 rad/s^2. The wheel starts at rest at t=0, and a chalk line drawn to a point P on the rim of the hweel makes an angle of 57.3 ith the horizontal at this time. At t 2s, find (a) the angular speed of the wheel, (b) the linear velocity and tangential acceleration of P, and (c) the position of P.

a. 8 rad/s
b. 2.4 m/s, 1/2 m/S^2
c. ? :(
I did parts a and b, but do not understand how to do part c.

Homework Equations

wf^2 = wi^2 + 2 \alphatheta

The Attempt at a Solution

wf^2 = wi^2 + 2 \alphatheta
(8 rad/s)^2 = 0 + 2(4 rad/s^2)theta
theta = 8 radians
Convert to degrees--> 458 degrees
458 - 360= 98.36 degrees above the horizontal


Could someone please tell me what I'm doing wrong? I'm pretty sure I'm doing something wrong. Haha. . .

Thank you in advance!

 

[rl.bhat]

Use the formula

θ = θο + ωi*t + 1/2*α*t^2.