Two boys A and B are sitting on opposite sides of a horizontal turntable which rotates a...

Two boys A and B are sitting on opposite sides of a horizontal turntable which rotates at a constant counterclockwise angular velocity as seen from above. Boy A throws a ball toward B by giving it a horizontal velocity u relative to the turntable toward B. Assume that the ball has no horizontal acceleration once released and write an expression for the magnitude of the acceleration a_rel which B would observe the ball to have in the plane of the turntable just after it is thrown. Sketch the path of the ball on the turntable as observed by B.