Twelve wires of equal lenghts (each 10 cm) are connected in the form of a skeleton cube. If the cube is moving with a velocity 0.05 `m//s`, find the emf induced in each arm of the cube if the cube moves parallel to field. If the cube moves perpendicular to the field, What will be the induced e.m.f. in each arm ? Given B=5 Wb/m^2

Explanation

For generation of motional emf, B, l and v should be mutually perpendicular to each other or they must have mutually perpendicular component. If any of the two quantities are parallel, emf is not induced. In this case, velocity of each conductor is parallel to the magnetic field B. So no emf will be induced in case (a).
The arms AE, CG, HD and GC are parallel to the velocity v. So, no emf will be induced in them.
The arms AB, DC, EF and HG are parallel to the field B, so no emf is induced in these arms also.
The arms AD, BC, EH and FG are perpendicular to both B and v. So, emf will be induced in these arms and is given by
`epsilon=Blv`
Here, `B=0.06 Wb // m^(2)`, l=5 cm =0.05 m, `v=10 m // s`
`:. epsilon = 0.06 xx 0.05 xx 10= 0.003 V`