Electric field given by the vector `vec E = x hat i + y hat j` is present in the x y plane. A small ring carrying `+Q`, which can freely slide on a smooth nonconducting rod, is projected along the rod from the point `(0, L)` such that it can reach the other end of the rod. What minimum velocity should be given to the ring ? (Assume zero gravity).
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Options

A. `(QL^(2)//m)^(1//2)`
B. `2(QL^(2)//m)^(1//2)`
C. `4(QL^(2)//m)^(1//2)`
D. `((2QL^(2))/(m))^(1//2)`

Answer

D