What Force Does a Charged Particle Experience in a Magnetic Field?

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goomer
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Homework Statement



A charged particle traveling with a velocity v in a magnetic field B experiences a force F that must be:

A. parallel to v
B. perpendicular to only v
C. parallel to v-B
D. parallel to B
E. perpendicular to v x B


Homework Equations



Requires this right hand rule, I believe:
http://upload.wikimedia.org/wikipedia/commons/6/6f/Right_Hand_Rule_vBF2.PNG

The Attempt at a Solution



Looking at the diagram, I'd say that the force should be perpendicular to both the force and the velocity and I had originally picked E. E is not correct, so would the right answer be B? But that would mean that force is not perpendicular to v and it very clearly is...
 
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goomer said:

Homework Statement



A charged particle traveling with a velocity v in a magnetic field B experiences a force F that must be:

A. parallel to v
B. perpendicular to only v
C. parallel to v-B
D. parallel to B
E. perpendicular to v x B


Homework Equations



Requires this right hand rule, I believe:
http://upload.wikimedia.org/wikipedia/commons/6/6f/Right_Hand_Rule_vBF2.PNG

The Attempt at a Solution



Looking at the diagram, I'd say that the force should be perpendicular to both the force and the velocity and I had originally picked E. E is not correct, so would the right answer be B? But that would mean that force is not perpendicular to v and it very clearly is...
Are you sure you copied down the problem correctly? Including the choices? The answer isn't E, but it's not quite any of the other others either, as they're presently written.
 
tiny-tim said:
goomer, can you check the wording of C ?

Oh sorry! C should be "Parallel to vxB".

I assume is C is the right answer then? If so, why?
 
goomer said:
Looking at the diagram, I'd say that the force should be perpendicular to both the [field] and the velocity …

from the pf library
The cross product of two vectors [itex]\mathbf{A}[/itex] and [itex]\mathbf{B}[/itex] is a third vector (strictly, a pseudovector or axial vector) [itex]\mathbf{A}\times\mathbf{B}[/itex] perpendicular to both of the original vectors … :wink: