Tagged Questions
1
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1answer
46 views
Induced voltage of a conductor in a magnetic field
A book which I referenced for Electrical Machinery states that the voltage induced in a conductor inside a magnetic field is given by
$$ \mathcal{E}=(\mathbf{v} \times \mathbf{B})\cdot \mathbf{l}$$
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4
votes
2answers
115 views
Vector potential
I have difficulty understanding the following vector calculus example. Text can be found here. It is the 5th Q&A -- starting with equation (31.1035).It concerns finding the vector potential of a ...
0
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2answers
184 views
Why or how is cross product used?
I do not understand how does the result of two vectors acting on a particle require me to take the cross product to find the resultant.
Won't the actual force on the particle be the result of the ...
1
vote
3answers
86 views
Currents and magnets
I've watched this video on YouTube by Sixty Symbols entitled "Currents and Magnets". In the video, the professor demonstrates the expansion of a wire due to current heating it up and he also ...
2
votes
1answer
502 views
Which are other anomalies like Divergence of 1/r^2?
As one might have learned in the basic science (ex. Electrodynamic
theory), when we apply the divergence theorem to the vector function
like 1/r^2 with it pointing in the radial direction (like ...
1
vote
2answers
224 views
Potential of surface charge
I have a question about the $ \hat{n} $ in this formula $\sigma = P \dot{}\hat{n}$.
Why do sometime in my book they get $\sigma = P \cos{\theta}$ for a sphere. Isn't $\hat{n} = r$ ?
And then in ...
1
vote
1answer
145 views
Is there a more clever way to apply the cross product of two vectors to magnetism?
I am just beginning to learn magnetism and my book used two ways to define the force caused by the magnetic field, brushing over the latter.
The first:
$$F = q v B \sin (\theta).$$
And:
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0
votes
3answers
713 views
Direction of Magnetic force from a current running through a coil of wire
What is the direction is the magnetic force vectors pointing from a coil of wire that has current running through it?
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