Large ships often have circular structures in their windshields, as shown in FIGURE 6-59. What is their purpose? Called clear view screens, they consist of a glass disk that is rotated at high speed by a motor (in the center of the circle) to disperse rain and spray. If the screen has a diameter of 0.39 m and rotates at 1700 rpm, the speed at the rim of the screen is 35 m/s. What is the centripetal acceleration at the rim of the screen? (A large centripetal acceleration keeps liquid from remaining on the screen. For comparison, recall that the acceleration due to gravity is 9.81 m/s2.)