What is motional $emf$?

(N/A) Motional $emf$ is the electromotive force $(emf)$ induced in a conductor when it moves through a magnetic field.
When a conductor of length $l$ moves with a velocity $v$ perpendicular to a uniform magnetic field $B$,the magnetic force on the free electrons causes a charge separation,creating an electric field.
The induced $emf$ is given by the formula $\varepsilon = Blv$,where $B$ is the magnetic field strength,$l$ is the length of the conductor,and $v$ is the velocity of the conductor perpendicular to the field.