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A horizontal magnetic field B is produce...

A horizontal magnetic field `B` is produced across a narrow gap between the two square iron pole pieces. A closed square loop of side a, mass `m` and resistance `R` is allowed to fall with the tope the lopp in the field. The loop attians a terminal velocity equal to :

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Induced emf in the loop, when it is falling with terminal velocity
`e = BVa`, `i = (e )/(R ) = (Bva)/(R )`
Vertically upward force experienced by loop due to this
`F = Bia` , `B((Bva)/(R ))a`, `= (B^(2)va^(2))/(r )`
When the loop attains velocity `'v'`
`mg = (B^(2)va^(2))/(R )`, `V = (mgR)/(B^(2)a^(2))`
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