What Power Is Needed To Accelerate An Object To 2.7 rad/s In 5.2 s?

[n.hirsch1]

Homework Statement

See the image attached
What power must be applied to this object to accelerate it from rest to an angular speed of 2.7 rad/s in 5.2 s about the x axis?

Homework Equations

P = W / t - torque * angular velocity

The Attempt at a Solution

P = [(0.5 m)*(7 kg)*(acceleration)] * 2.7 rad/s
I don't know how to find acceleration or if I am doing this wrong all together. The right answer is 1.3 W. I tried plugging it into the motion equation v = vo + at to get a, that gave me the wrong answer.

 

[Delphi51]

The work goes into making the system have kinetic energy. Your starting point should be P = KE/time. Now you just have to figure out how much rotational kinetic energy it has when ω = 2.7 rad/s.