Moving electron under two magnetic fields

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merdeka
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Homework Statement
A coil ##\vec{B}## a current of intensity ##i## created in ##M## a magnetic field ##\vec{B}_1##. A magnet ##A## created in ##M## a magnetic field ##\vec{B}_2## .

What is the force undergone by a charge particle ##q## with a velocity ##\vec{v}## that is in ##M## at time ##t## ?

Taking into account the mass of the electron.
Relevant Equations
##F=q\cdot v\cdot B\cdot\sin(\vec{v},\vec{B})##
Diagram of magnetic field vectors at point M: B1 and B2 with resultant B, velocity v pointing left, a dashed angle alpha, and a bar magnet labeled N and S with a deltaB2 arrow, plus a coil on the right.


In this question, I would have to calculate the force in respect to time. However, the question gives me the value of the mass of the electron. In my attempt, I didn't take that into account. I just replaced ##v## with ##\frac{d}{t}## and made the Lorentz force undergone by the particle inversely proportional, but this is probably not correct.
 
Last edited:
Hi,

merdeka said:
the force in respect to time
I think the exercise asks for the force at time ##t## and doesn't want you to calculate a trajectory. (For which there is no information given anyway)
 
BvU said:
Hi,

I think the exercise asks for the force at time ##t## and doesn't want you to calculate a trajectory. (For which there is no information given anyway)
The question didn't give any information or value for a point in time.
 
So we agree on that. At time ##t##, position, velocity and field are known. There is no ##d## in the problem and you don't need it. Calculate in a straightforward manner with the equation you mention..