Answer:
Current flowing in the wire is 1680 A
Step-by-step explanation:
It is given length of wire l = 3.5 m
Mass of the wire m = 0.03 kg
Magnetic field B = 0.00005 Tesla
Acceleration due to gravity

Mg force acting on the wire will be equal to Lorentz force acting on the wire.
Therefore



Therefore current flowing in the wire is 1680 A