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3. (10 marks) A turntable is rotating counterclockwise at a constant angular speed with respect to the ground (which is an inertial frame). The turntable is perfectly flat, and its surface is frictionless. A puck is placed on the turntable at a distance R from its centre, and at rest with respect to the ground. Obviously, because there is no friction, the puck remains at rest with respect to the ground, and the turntable rotates underneath the puck. Therefore, with respect to the turntable, the puck must move clockwise in a circle of radius R at an angular speed 2. (a) Draw a free-body diagram of all the horizontal forces acting on the puck in the reference frame of the turntable. Your diagram should indicate the correct direction of these forces relative to the path of the puck, and the forces should be labelled (i.e. don't just scribble some arrows coming out of a dot in random directions) (b) Solve the equation of motion for the puck in the reference frame of the turntable, and show that it does indeed move clockwise in a circle of radius R and angular speed 2.