One question about rotational speed

AI Thread Summary
The discussion revolves around a physics problem involving a casino roulette wheel and a ball, focusing on their angular speeds and the effects of friction. The wheel starts at 15 rad/s and slows down at 5 rad/s², while the ball spins at 20 rad/s in the opposite direction. The key question is how many times the ball passes the "00" mark after 3 seconds, disregarding the ball's friction. Participants emphasize the need to calculate the relative angular speeds and the total angular displacement over the given time. The conversation highlights the importance of understanding angular motion concepts to solve the problem effectively.
wowolala
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Homework Statement




A casino roulette wheel is set spinning with an initial angular speed of 15 rad/s. The ball is set spinning in the opposite direction with a constant angular speed of 20 rad/s as the
"00" passed by. If friction makes the wheel slow down with an angular acceleration of 5 rad/s^2, How many times does the ball pass by the "00" after 3 seconds? ( Ignore the slowing down of the ball due to friction. )


thx so much... could somebody help me to solve this quesion?
 
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