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A particle is moving at a constant speed V from a large distance towards a concave mirror of radius R along its principal axis. Find the speed of the image formed by the mirror as a function of the distance x of the particle from the mirror.

given

Radius of the concave mirror= R


Focal length of the mirror,


Velocity of the particle,



Let velocity of the image is represented as V’


The distance of the object from the mirror, u= -x


Using mirror equation,











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