Four identical positive point charges `Q` are fixed at the four corners of a square of side length `l`. Another charged particle of mass `m` and charge `+q` is projected towards centre of square from a large distance along the line perpendicular to plane of square. The minimum value of initial velocity `v_(0)` (in m/s) required to cross the square is ?
`(m = 1 gm, l = 4 sqrt(2) m, Q =1 mu c, q = 0.5 muc)`

Answer

3