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A disc of radius 10 cm is rotating abou...

A disc of radius 10 cm is rotating about its axis at an angular speed of 20 rad/s. Find the linear speed of
a. a point on the rim,
b. the middle point of the radius.

Text Solution

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The correct Answer is:
A, B
Radius of disc=10cm=0.1m
Angular velocity =20 rad/s
`:.` Linear velocity on the rim
`=omegar=20xx0.1=2m/s`
`:.` linear velocity at the middle of radius
`(omegar)/2=20xx((0.1)/2)`
`=1m/s`
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HC VERMA-ROTATIONAL MECHANICS-Exercises
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  4. A disc rotates about its axis with a constant angular acceleration of ...

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  8. Find the moment of inertia of a pair of spheres, each having a mass m ...

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  9. The moment of inertia of a uniform rod of mass 0.50 kg and length 1 m ...

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  10. Find the radius of gyration of a circular ring of radius r about a lin...

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  11. The radius of gyration of a uniform disc about a line perpendicular to...

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  16. When a force of 6.0 N is exerted at 30^@ to a wrench at a distance of ...

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  17. Calculate the total torque acting on the body shown in figure about th...

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  18. A cubical block of mass M and edge a slides down a rougg inclined plan...

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  19. A rod of mass m and length L , lying horizontally is free to rotate ab...

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