What causes the Magnus effect?

The Magnus effect is caused by the rotation of a spinning object, such as a ball or cylinder, through a fluid (such as air or water). As the object spins, it creates a pressure difference between the side spinning in the same direction as the fluid flow and the side spinning against the fluid flow. This pressure difference results in a sideways force, known as the Magnus force, which causes the object to curve or swerve in the direction of the spin.

The Magnus effect is the deviation of a spinning object from its trajectory due to the interaction between the spin of the object and the flow of a fluid around it. The cause of this effect is the Bernoulli principle, which states that the pressure of a fluid is inversely proportional to its velocity.

When a spinning object moves through a fluid, the fluid is pushed away from the surface of the object by the centrifugal force of the spin. This creates a region of low pressure around the object. On the side of the object that is moving in the direction of the spin, the fluid velocity is higher than on the opposite side. According to Bernoulli's principle, the pressure is lower on the side with the higher fluid velocity. This difference in pressure creates a force that pushes the object in a direction perpendicular to both the direction of the spin and the direction of the fluid flow. This is the Magnus effect.

The Magnus effect is used in a variety of applications, such as the flight of airplanes and the control of golf balls. In the case of an airplane, the spinning of the propellers creates a Magnus effect that helps to lift the plane off the ground. In the case of a golf ball, the spinning of the ball creates a Magnus effect that causes the ball to curve in the direction of the spin.