Step 1:

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(a)

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The angular velocity of the phonograph turntable is \"\".

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The distance from the axis of rotation is \"\".

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Convert the angular velocity from rev/min to rad/sec.

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\"\"

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Find the angular acceleration.

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Angular acceleration : \"\",

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where \"\" is the distance from the center of axis.

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\"\" is the angular velocity.

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\"\"

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Angular acceleration of the block is \"\".

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Solution:

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Angular acceleration of the block is \"\".

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 \"\"

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Step 1:

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(b)

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The block exerts a force equal to the force due to friction.

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\"\"

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Coefficient of static friction is 0.06837.

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Solution:

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Coefficient of static friction is 0.06837.

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Step 1:

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(c) 

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The angular velocity of the phonograph turntable starts from rest.

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Velocity reaches \"\" in 0.25 sec.

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Angular velocity : \"\"

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The distance from the axis of rotation is \"\".

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Find the angular acceleration.

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Angular acceleration : \"\",

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where \"\" is the distance from the center of axis.

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\"\" is the angular acceleration.

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\"\"

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Step 2:

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Total angular acceleration.

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\"\"

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Total acceleration of the block is \"\".

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Solution:

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Angular acceleration of the block is \"\".

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Step 1:

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(d)

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The block exerts a force equal to the force due to friction.

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\"\"

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Coefficient of static friction is 0.10399.

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Solution:

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Coefficient of static friction is 0.10399.