A ball is aatached to a string that is attached to a pole . when the ball is hit, the string wraps around the pole and the ball spiral inwards sliding on frictionless surface . Neglecting air resistance .
I think mechanical energy is conservesd as there is no friction and I also think that angular momrntum about centre of pole is conserved when ball swings around the pole .
But in my book it is written as angular momentum about centre of pole is notconserved when ball swings around the pole .
I could not understand this .