A wheel is rotating at a uniform clockwise speed of 2 rad/s when a variable torque is applied to its shaft at time t=0. As a result there is a clockwise angular acceleration \alpha which increases in direct proportion to the angle \Theta through which the wheel turns from the instant t=0. After 16 complete turns from this time the angular acceleration is 4rad/s^2. Determine the angular velocity w of the wheel when this condition is reached.