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Angular momentum physics?

A solid cylinder with a mass of 266 kg and radius 0.060 m is rotating with an angular speed of 84.0 rad/s about an axis passing through its center and perpendicular to its end faces. The rotation of the cylinder is slowed down by a factor of 2 by applying a tangential frictional force to it for 5.30 s. What is the magnitude, in N, of the friction force applied to the cylinder?

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  • 2 years ago
    Favorite Answer

    Torque = I*α = ½*266*0.06² *α = 0.4788*α = F*0.06

    α = (84-42)/5.3 = 7.92453

    0.4788*7.92453/0.06 = F = 63.2N

  • 2 years ago

    Let’s use the following equation to determine the friction force.

    Force * time = moment of inertia * change of angular velocity

    The following equation is used to calculate the moment of inertia of a solid cylinder.

    I = ½ * m * r2 = ½ * 266 * 0.06^2 = 0.4788

    Change of angular velocity = 84 – 42 = 42 rad/s

    Force * 5.30 = 0.4788 * 42

    F = 20.1096 ÷ 5.30

    The force is approximately 3.79 N. I hope this is helpful for you.

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