8. What is the centripetal acceleration of an object on the end of an 0.8 m string rotating at a constant rate of 4 times a second? 9. A 3 kg mass is travelling in a circle of 0.2 m radius with a speed of 2 m/s. What is the centripetal acceleration? 10. An object moves in a circular path at a constant speed. Which of the following is true? 11. A wave has a speed of 300 m/s and a frequency of 88.9. What is the wavelength