2. [15 points] Multiple-choice questions. Refer to the figures below.
申論題內容
(2) A rectangular plate swings from arms of equal length as shown below. What is the magnitude of the angular velocity of the plate? (a) O rad/s (b) I rad/s (c) 2 rad/s (d) 3 rad/s (e) Need to know the location of the center of gravity.