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Feldoh
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I was just wondering, since my textbook doesn't really explain it too well, what velocity is part of the equation F = qv x B? Is it the drift velocity, or...?
Snazzy said:There is only a force if the velocity of a particle is perpendicular to the direction of the magnetic field.
Practicly you would use v relative to the charge that causes B, because you can easily calculate B in that system.Feldoh said:I was just wondering, since my textbook doesn't really explain it too well, what velocity is part of the equation F = qv x B? Is it the drift velocity, or...?
Sorry, but we don't use relative velocity as you said in this post,we only use net ACTUAL velocity of chargeLojzek said:Practicly you would use v relative to the charge that causes B, because you can easily calculate B in that system.
In general you can use any inertial coordinate system and measure the speed of the charge q in that system. You might get different magnetic force F in diferent systems, but this is not a problem, since B and E are also dependent on the system and particle feels both electric and magnetic force. For systems moving relative to each other at nonrelativistic speeds you will get aproximately the same electromagnetic force F. If speeds are relativistic, you get different F in different systems since a relativistic particle has different acceleration in different inertial systems (but those different forces will still describe the same movement).
You did not read my post carefully. I used the phrase "relative velocity" because it may not be clear which system of coordinates we should choose. In this case "actual velocity" has little meaning.mr.survive said:Sorry, but we don't use relative velocity as you said in this post,we only use net ACTUAL velocity of charge
Feldoh said:I was just wondering, since my textbook doesn't really explain it too well, what velocity is part of the equation F = qv x B? Is it the drift velocity, or...?
Phrak said:Please correct me if I'm wrong. For a wire, v serves as the drift velocity in equation F = qv x B, even if it isn't an actual velocity. With this assignment, q must be interpreted as the amount of current entering the wire, per unit time.
Importantly, with these assignments, q is not the charge carried by each particle.
I realize that this isn't the usual correspondence of variables, but it seems to serve.
Maybe you were really looking for this equation: F = iL x B, the force on a current carrying wire of length, L within B.
A magnetic field is an invisible force field that surrounds a magnet or a moving electric charge. It is created by the movement of electric charges and is responsible for the attraction or repulsion between magnets and other electrically charged objects.
The strength of a magnetic field is measured using a unit called tesla (T), which is equivalent to one newton per ampere-meter. Another common unit of measurement is gauss (G), with 1 T equal to 10,000 G.
Electric currents create magnetic fields, and magnetic fields can induce electric currents. This relationship is described by Maxwell's equations and is the basis for many modern technologies such as electric motors and generators.
The strength of a magnetic field directly affects the force it exerts on other objects. The stronger the magnetic field, the greater the force between two objects. This force is also dependent on the distance between the objects and the orientation of their magnetic poles.
Magnetic fields have a wide range of applications, including in electric motors, generators, MRI machines, particle accelerators, and magnetic levitation trains. They are also used in everyday items such as credit cards and speakers.