Answer: The force that makes the ball move in a circle around the pole is an angular force known as CENTRIPETAL FORCE.
Step-by-step explanation:
When a stone is attached to a string, just as in the tetherball game, and whirled round at constant speed in a horizontal circle, the stone moves with constant speed but at different directions and acceleration ( as the ball is hit by different players) directed towards the center of the circle due to the tension in the spring that produces a force.
The force that is required to keep the object ( ball) moving in this circular path is called the centripetal force. It is inversely proportional to the radius curvature (r) which is formed by the rope that ties the ball to the pole. Therefore, the force increase as the radius decreases.
Hence,
F= mv²/ r
Where F= centripetal force
m= mass
v= velocity
r= radius of curvature
Other examples of centripetal force includes
--> a car moving in a circular path,
--> the revolution of the planets round the sun,