Chap 5 Sample Problems 1 ) A car travels around a curve with radius of 52.25 m at 30.0 m/s. a) What is the centripetal acceleration? b ) If the car has a mass of 975 kg, what is the centripetal Force? 2) A 0.1500 kg bob is attached to a string and swung in a vertical circle with radius of 1.250 m at a speed of 5.250 m/s. What is the tension in the string: when the bob is at the top? When the bob is at the bottom? C When the bob and string are horizontal