Wheel on a Frictionless Axis?

Question

A wheel of radius 0.20 m is mounted on a frictionless horizontal axis. The rotational inertia of the wheel about the axis is 0.050 kg · m2.A massless cord wrapped around the wheel is attached to a 2.0 kg block that slides on a horizontal frictionless surface. If a horizontal force of magnitude P = 3.0 N is applied to the block as shown in Fig. 11-35, what is the magnitude of the rotational acceleration of the wheel? Assume that the string does not slip on the wheel.

Answer 1

Look at a FBD of the block
3-T=2*a

and the wheel
T*0.2=0.05*alpha
where alpha = a/r

Alpha =4.62

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