Editing Magnus effect (section)

===Pressure differences===
The air's [[viscosity]] and the surface roughness of the object cause the air to be carried around the object. This adds to the air velocity on one side of the object and decreases the velocity on the other side. [[Bernoulli's principle]] states that under certain conditions increased flow speed is associated with reduced pressure, implying that there is lower air pressure on one side than the other. This pressure difference results in a force perpendicular to the direction of travel.<ref name=Halliday2>{{cite book

| last = Halliday
| first = David
| title = Fundamentals of Physics
| publisher = John Wiley and Sons
| edition = 3rd Extended
| date = 1988
| location = 
| pages = 278–279
| language = English
| quote=Without viscosity and the boundary layer, the spinning ball could not carry air around in this way... the velocity of air below the ball is less than that above the ball. From Bernoulli's equation, the pressure of air below the ball must be greater than that above, so the ball experiences a dynamic lift force. }}</ref>
{{multiple image
|image_style=border:none;
|align=center
|image1=08. Магнусов ефект.ogv
|caption1=While the pipe rotates, as a consequence of fluid friction, it pulls air around it. This makes the air flow with higher speed on one side of the pipe and with lower speed on the other side.
| image_gap = 20
|image2=Magnus effect.gif
|caption2=Magnus effect in a particle simulation of a 2D liquid
}}
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