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A block X of mass 0.5 kg is held by a long massless string on a frictionless inclined plane of inclination 30° to the horizontal. The string is wound on a uniform solid cylindrical drum Y of mass 2 kg and radius 0.2 m as shown in the diagram. The drum is given an initial angular velocity such that the block X starts moving up the plane. Find the tension in the string during motion. At a certain instant of time, the magnitude of the angular velocity of Y is 10 rad s-1. Calculate the distance travelled by X from that instant of time unit it comes to rest.


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Important Questions on Systems of Particles and Rotational Motion

MEDIUM

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The speed of the sliding end P when θ=60° is

MEDIUM
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EASY
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HARD
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MEDIUM
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EASY
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MEDIUM
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MEDIUM

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A uniform rod of length ' ' is pivoted at one of its ends on a vertical shaft of negligible radius. When the shaft rotates at angular speed ω the rod makes an angle θwith it (see figure). To find θ equate the rate of change of angular momentum (direction going into the paper) m212ω2sinθ about the centre of mass (CM) to the torque provided by the horizontal and vertical forces FHand Fv about the CM. The value of θ is then such that:

MEDIUM
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HARD
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MEDIUM
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HARD
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MEDIUM
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MEDIUM

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EASY
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EASY
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EASY
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MEDIUM
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EASY
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