Angular Speed of Sign Before Impact: Kevin's Solution

AI Thread Summary
The discussion focuses on calculating the angular speed of a rectangular sign just before it is struck by a snowball. The sign, with a mass of 2.40 kg and a vertical dimension of 45.0 cm, swings without friction and has a maximum angular displacement of 25.0° from vertical. A snowball weighing 520 g and moving at 160 cm/s collides with the sign's lower edge. The key to solving the problem lies in applying the conservation of angular momentum at the moment of impact. Participants are encouraged to show their work for further assistance in the calculations.
klopez
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A thin, uniform, rectangular sign hangs vertically above the door of a shop. The sign is hinged to a stationary horizontal rod along its top edge. The mass of the sign is 2.40 kg and its vertical dimension is 45.0 cm. The sign is swinging without friction, becoming a tempting target for children armed with snowballs. The maximum angular displacement of the sign is 25.0° on both sides of the vertical. At a moment when the sign is vertical and moving to the left, a snowball of mass 520 g, traveling horizontally with a velocity of 160 cm/s to the right, strikes perpendicularly the lower edge of the sign and sticks there.

(a) Calculate the angular speed of the sign immediately before the impact

I have absolutely no clue on how to the w. If anyone can please enlighten me, it would be greatly appreciated. Thanks

Kevin
 
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Use conservation of angular momentum at the moment of impact.

The sum of the angular momenta of the snowball and the sign just before the impact is equal to the angular momentum of the sign just after the impact. If you need more help, you have to show some work now, though this should be enough.
 

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