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Induced drag:- is a sort of drag caused by the wing's generation of lift.
One cause of this drag is the flow near the wing tips being distorted as a result of the pressure difference between the top and the bottom of the wing, which in turn results in swirling vortices being formed at the wing tips.
The induced drag is an indication of the amount of energy lost to the tip vortices .
The swirling vortices cause downwash near the wing tips, which
reduces the overall lift coefficient of the wing
The picture below shows the downwash caused by an aircraft.
This image of the vortex trailing from the right wingtip of an agricultural aeroplane clearly shows the region of downwash to the left of the vortex core, and the region of upwash to the right of the core. (It also shows air above the core moving left, and below the core, moving right