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Question
A sphere can roll on a surface inclined at an angle θ if the friction coefficient is more than \[\frac{2}{7}g \tan\theta.\] Suppose the friction coefficient is \[\frac{1}{7}g\ tan\theta.\] If a sphere is released from rest on the incline, _____________ .
Options
it will stay at rest
it will make pure translational motion
it will translate and rotate about the centre
the angular momentum of the sphere about its centre will remain constant
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Solution
it will translate and rotate about the centre
The given coefficient of friction \[\left(\frac{1}{7}g\ tan\theta\right)\] is less than the coefficient friction \[\left(\frac{2}{7}g\ tan\theta\right)\] required for perfect rolling of the sphere on the inclined plane.
Therefore, sphere may slip while rolling and it will translate and rotate about the centre.
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