Question

A negatively charged electron enters a uniform magnetic field. If the electron's initial velocity is from right to left, then what is the direction of the magnetic force acting on the electron when it first enters the field? Explain.

Answer 1

Lorentz force, \(\vec{F}\) is given by:
\(\vec{F} = q(\vec{E} + \vec{v}\times\vec{B})\)
\(q\) is charge (remember the electron is negative!), \(\vec{E}\) is electric field, \(\vec{v}\) is velocity, \(\vec{B}\) is magnetic field.

Do you know how to do a cross product?

Answer 2

In case not, you can use your right hand to remember.

Answer 3

We are not told the direction of the magnetic field?

Answer 4

the magnetic field is directed into the page

Answer 5

but i figured it out. thank you