A1.5 kg tether ball is hit so that it circles the pole with an angular speed of 4m/s

Well, you didn't ask a question, and 4 m/s is not an angular speed.
So all I can offer is a couple of observations:

1). The tension in the rope is

      M V² / R  =  (1.5 kg) x (4 m/s)² / R

                     =  (24 kg-m²/s²) / (distance of the ball from the pole).

2).  Tetherball was the only thing I played at camp,
       more than 60 years ago, and I loved it !
       It was a tough game, because we had to skin
       our own T.Rex and use his hide to make the ball
       and his guts for the rope.