Figure shows a horizontal wire MN of length I and mass mis placed in a magnetic field B. The ends of wire are bent and dipped in two bowls containing Hg which are connected to an external circuit as shown. If key is pressed for a short time `delta t`.due to which a charge q suddenly flows in the circuit. Find the maximum height above initial level the wire MN, it will jump.

Answer

`[(B^(2)q^(2)l^(2))/(2m^(2)g)]`