# Magnetic Field and Forces

1. Apr 14, 2008

### soul5

1. The problem statement, all variables and given/known data

At a point near the equator, the Earth's magnetic field is horizontal and points to the north. If an electron is moving vertically upward at this point, what is the direction of the magnetic force acting on this? Explain.

2. Apr 14, 2008

### Mentz114

Use the right-hand rule to find the direction of the force. If you don't know what the RHR is, look it up in Google.

3. Apr 14, 2008

### soul5

I'm confused don't I use left hand rule when dealing with electrons?

4. Apr 14, 2008

### pinkenergy

no, no need for left hand rule. use RHR and reverse the results.

5. Apr 14, 2008

### physicsbhelp

yes, listen to pinkenergy, use the right hand rule.

6. Apr 14, 2008

### pinkenergy

but lol...bc i am new to this, i cant say with certainty bc i kinda asked the SAME question a few threads below yours. i think magnetic FORCE would be pointing to the left for a proton, so it would be pointing to the right for an electron.

Last edited: Apr 14, 2008
7. Apr 14, 2008

### jcpwn2004

I'm kinda confused by which way the magnetic field is pointing but basically use your right hand and point it in the direction the electron is moving and then rotate your arm so that your palm is facing the direction of the magnetic field. Whatever you get for this is the opposite of the answer since it's an electron.

8. Apr 16, 2008

### soul5

I'm lost don't I use my palm to find force? My palm is magnetic force not field.

9. Apr 16, 2008

### BNoelCMU

It's just simply F = q(vxB). The right hand rule always works, ALWAYS, you just have to keep in mind what the charge on the electron is (negative or positive?). The right hand rule works every time. That is why it is a rule.