A Ball Attached to a String Starts at Rest and Undergoes

Multiple Choice

A ball attached to a string starts at rest and undergoes a constant angular acceleration as it travels in a horizontal circle of radius 0.30 m. After 0.65 sec, the angular speed of the ball is 9.7 rad/s. What is the tangential acceleration of the ball?

A) 4.5 m/s²
B) 0.32 m/s²
C) 15 m/s²
D) 7.6 m/s²
E) 28 m/s²