Answer:
11.7 im pretty sure. i did the work so it should be correct
Metal bar is aligned along East- West direction and it is dropped vertically down
So its velocity is along -Z direction,
Now the Earth's magnetic field is towards north so its towards +Y direction
now we have formula for force on a moving charge
v = - z direction
B = + y direction
now by the above formula
So force is towards East
so all positive charge is towards East end