What’s Going on?
Notice that when only a part of the ball is out of the air stream you can feel the ball being sucked back. If you release the ball, it will move back to the center of the air stream and stay afloat.
When the ball is pulled partly out of the air stream, the air that is moving fast along the side of the ball exerts less sideways pressure on the ball than the still air in the room. The greater pressure of the surrounding air pushes the ball back to the center. The ball stays afloat because the air from the blower exerts an upward force on the ball. The maximum capacity of the blower makes the ball stay at a certain height. In other words, when a stronger source of moving air is used, the ball will float higher.
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