Question

In which direction does a magnetic force act on an electron that is moving in the positive x-direction in a magnetic field pointing in the positive z-direction?

A) any direction in the xy-plane
B) the negative y-direction
c) the negative x-direction
D) the positive y-direction


a particle with charge q is at rest when a magnetic field is suddenly turned on. The field
points in the z-direction. What is the direction of the net force acting on the charged particle?

a) In the z-direction.
b) There is no force on the particle.
c) In the y direction
d) In the x direction

Answer 1

Are you familiar with the Fleming left hand rule?
If you are, then you just need to apply it to the questions above.
Note: a moving electron is equal to a electric current.
Note: a non-moving electric particle will not experience the magnetic force if it is not moving (i.e. there is no electric current)
Do you need further help?

Answer 2

for the 2nd question, i think the answer if there is no force since there is no velocity. for the 1st question, i did the right hand rule and got neg y direction, but im not sure if that's wrong since the particle is an electron.

Answer 3

For the second question, yes, there is no force as there is no current.
For the first, isn't it the left-hand rule since this isn't a generator?