12. An amusement park ride consists of a rotating vertical cylinder with rough canvas walls. The floor is initially about halfway up the cylinder wall as shown below. After the rider has entered and the cylinder is rotating sufficiently fast, the floor is dropped down, yet the rider does not slide down. The rider has mass of 50 kilograms, the radius R of the cylinder is 5 meters, the angular velocity of the cylinder when rotating is 2 radians per second, and the coefficient of static friction between the rider and the wall of the cylinder is 0.6. a) On the diagram above. draw and identify the forces on the rider when the system is rotating and the floor has dropped down. b) Calculate the centripetal force on the rider when the cylinder is rotating and state what provides that force. c) Calculate the upward force that keeps the rider from falling when the floor is dropped down and state what provides that force. d) At the same rotational speed, would a rider of twice the mass slide down the wall? Explain your answer.

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