While working as an intern in a blacksmith's shop, you realize that the brake on the sharpening stone (a stone uniform disk) is no longer working. To stop the rotation at the end of the day, you put your knowledge of physics to good use and use a steel axe to stop the rotation. You press the steel axe against the stone using a radial force of 19.5 N. The stone is originally rotating at a rate of 85 revolutions per minute (out of the page), has a radius of 0.350 m, and a mass of 91.0 kg. Choose out of the page to be positive. a) Given a coefficient of kinetic friction between the stone and the axe equal to 0.20, what is the angular acceleration of the sharpening stone? b) What angular displacement did the stone turn through from its initial angular speed to when the stone stops rotating?

While working as an intern in a blacksmith's shop, you realize that the brake on the sharpening stone (a stone uniform disk) is no longer working. To stop the rotation at the end of the day, you put your knowledge of physics to good use and use a steel axe to stop the rotation. You press the steel axe against the stone using a radial force of 19.5 N. The stone is originally rotating at a rate of 85 revolutions per minute (out of the page), has a radius of 0.350 m, and a mass of 91.0 kg. Choose out of the page to be positive. a) Given a coefficient of kinetic friction between the stone and the axe equal to 0.20, what is the angular acceleration of the sharpening stone? b) What angular displacement did the stone turn through from its initial angular speed to when the stone stops rotating?