A uniform 5.50kg square solid wooden gate 2.00m on each side hangs vertically from a frictionless pivot at the center of its upper edge. A 1.30kg raven flying horizontally at 5.00m/s flies into this door at its center and bounces back at 2.50m/s in the opposite direction.
What is the angular speed of the gate just after it is struck by the unfortunate raven? (radians/sec)
What is the angular speed of the gate just after it is struck by the unfortunate raven? (radians/sec)
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Moment of inertia of the gate
= m a^2 /3
= 5.5 * 2 ^2 / 3
= 7.33
momentum of the raven
= 1.3 [ 5 - ( -2.5)]
= 9.75
angular momentum of the gate
= MoI * angular speed of the gate
= 7.33 * w
7.33 w = 9.75
w = 1.33 rad /s ---answer
= m a^2 /3
= 5.5 * 2 ^2 / 3
= 7.33
momentum of the raven
= 1.3 [ 5 - ( -2.5)]
= 9.75
angular momentum of the gate
= MoI * angular speed of the gate
= 7.33 * w
7.33 w = 9.75
w = 1.33 rad /s ---answer