Lift force measurements in a Bernoulli funnel-ball experiment explained using the Bernoulli equation

Abstract The Bernoulli levitation demonstration using a funnel and a ball is widely used to teach the Bernoulli principle. But the claim is made in the literature that there are other effects than the Bernoulli principle, and that solving the problem requires numerical fluid physics calculations. We measure the upward-acting force in such an experiment for a selection of balls with radii from 19.67 to 39.07 mm, and with weights from 0.037 to 0.159 N. We find that, when the ratio of the radius of the ball to radius of the inner opening of the funnel is greater than 2, and the ratio of ball radius is less than the wider opening of the funnel, the Bernoulli effect dominates.