Magnus effect. In sum, the air flow around the side of the clockwise rotating cylinder, which rotates with the flow, is greater than on the other side causing a slight pressure difference. In the image that is on the underside of the cilinder, so that it experiences a downward force. The ball should have a horizontal speed -V toward <b>RIGHT</b>.
<p>Bartosz Kosiorek / <a href="https://en.wikipedia.org/wiki/User:Gang65" class="extiw" title="en:User:Gang65">Gang65</a> at <a class="external text" href="https://en.wikipedia.org">en.wikipedia</a>.
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Later version(s) were uploaded by <a href="https://en.wikipedia.org/wiki/User:Qutezuce" class="extiw" title="en:User:Qutezuce">Qutezuce</a> at <a class="external text" href="https://en.wikipedia.org">en.wikipedia</a>.
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