Forces Acting on a Swinging Ball in a Vertical Circle

Without a diagram, it is difficult to know which forces are being referred to. However, based on the description, there are two main forces acting on the ball at point P: tension (the force exerted by the string) and gravity (the force exerted by the Earth).

The tension force is directed towards the center of the circle (point O), as it is responsible for keeping the ball moving in a circular path. Therefore, one of the arrows representing the tension force would point towards point O.

The gravity force is directed downwards, towards the center of the Earth. At point P, this force would be perpendicular to the direction of motion of the ball. Therefore, one of the arrows representing the gravity force would point downwards.