Why a spinning ball curves in mid-air: the Magnus effect
30seconds
Clip a football with the side of your boot and it bends around a wall with nothing touching it in the air. A spinning ball drags air around with its surface, speeds the flow on one side and slows it on the other, and the lopsided push curves the path. This is the Magnus effect.
Aim a free kick wide of the post, dial in the spin, and watch it come back into the goal. Press Kick to see the curve, then reverse the spin or slow the ball down and see what changes.
Deep dive · 5 min
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