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Qvxb maybe not?

  • #1
qvxb maybe not??

Homework Statement


consider the example of a positive charge moving in the -z direction with speed with the local magnetic field of magnitude in the +z direction. Find , the magnitude of the magnetic force acting on the particle.
Express your answer in terms of , , , and other quantities given in the problem statement.


Homework Equations




f=qvXb yet this does not work ;/
This would be true if and were orthogonal. Instead, they are antiparallel--look back at the definition of the cross product if you still have trouble.

The Attempt at a Solution

 

Answers and Replies

  • #2
Doc Al
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f=qvXb yet this does not work ;/
This would be true if and were orthogonal.
[tex]\vec{F} = q\vec{v}\times \vec{B}[/tex]

works just fine, but that only equals qvB when v and B are orthogonal.
Instead, they are antiparallel--look back at the definition of the cross product if you still have trouble.
Sounds like good advice to me.
 
  • #3


[tex]\vec{F} = q\vec{v}\times \vec{B}[/tex]

works just fine, but that only equals qvB when v and B are orthogonal.

Sounds like good advice to me.
thank these things just confuse me at time :) lol easy to study for hard to do some how :/
 

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