Question

An electron is traveling horizontally toward the north in a uniform magnetic field that is directed vertically downward. In what direction does the magnetic force act on the electron? An electron is traveling horizontally toward the north in a uniform magnetic field that is directed vertically downward. In what direction does the magnetic force act on the electron?
A. west
B. east
C. downward
D. north
E. south
F. upward

Answer 1

Answer:

Towards east.

Explanation:

The magnetic force is given by :

$F=q(v\times B)$

q = -e is the charge on electron

v is he velocity of electron

B is the magnetic field

Electron is moving towards north and the magnetic field is directed vertically downward such that,

$B=-Bk$

$v=+vj$

$F=-e(vj\times (-Bk))$

Using right hand rule, the direction of magnetic force is towards east. So, the correct option is (B) "east".