Answer:
The magnetic force on the moving negative charge is towards the ceiling.
Explanation:
The magnetic force acting on a wire is given by the relation as follows :
[tex]F=q(v\times B)[/tex]
q is charged particle
v is velocity of charged particle
B is magnetic field
In this case, a negative charge is moving across a rook from south to north. A magnetic field runs from East to west.
q = -q
v =+j
B = -i
So,
[tex]F=-q(vj\times B(-i))[/tex]
Since, [tex]j\times i=-k[/tex]
So,
[tex]F=q(v\times B)(-k)[/tex]
So, the magnetic force on the moving negative charge is towards the ceiling.