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Grade 11Mechanics

A wheel of mass M and radius of gyration k (see Exercise 20) spins on a fixed horizontal axle passing through its hub. Assume that the hub rubs the axle of radius a at only the top- most point, the coefficient of kinetic friction being src=data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABUAAAAUCAIAAADtKeFkAAAAo0lEQVQ4je2TsRHEMAgEty4Koh6qoRmK8QeyLIyskWc++OTJGOl8yyFzfFf89Ve5glj0Nkxu/U7vCqgv+42+2r2yH/qdPExgBrr0L+jDZAIinaXrza14uc558EjrCtPwQ95nEQuyoJ26ota/FyanZaYftNzCGQklizqgayJjFUytRkidi1Uwpbp9XSvHq4eW1tNfeUuGxa4e6PuNM5oG8ev/9wP8tR0ReVpgHAAAAABJRU5ErkJggg== The wheel is given an initial angular velocity src=data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAABsAAAATCAIAAADu5eFvAAAAnklEQVQ4je2UwRGAMAgEry4Koh6qSTMUo4+MmiOiMePHGfkRYLkQEcvbhp9YzU2ghc+KQsxniG6C01o3GWQSsSjQyRuIZcRQE+Sm6lNiV3HdYEsAEI6RAO78ojvITdpIRoySToC7x7l86y3LTURVGpcFB1nUrn3rYzA1XEH9pOjOXYO5nQka6WOd3EIWSVOd3euBt35szZRplb7wN1sBdZ43h0mZJkQAAAAASUVORK5CYII= Assume uniform deceleration and find (a) the elapsed time and (b) the number of revolutions before the wheel comes to a stop

Profile image of Simran Bhatia
11 Years agoGrade 11
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1 Answer

Profile image of Aditi Chauhan
11 Years ago
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The time taken by the wheel to stop is:
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Here ω0 is the initial angular velocity of the wheel.
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It is important to note that the angle θ is in radians and not in revolution. Therefore one can convert the angle to revolutions by dividing θ by 2π as:
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