Tagged Questions
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Magnetic Field on a particle between two Helmholtz Coils
Given a Helmholtz coil of radius $R$ and with a current $I$, and assuming the coil is a circle centered at the origin in the $xy$-plane, what is the magnetic field on a particle at the point $(a, b, ...
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measuring electromagnetic induction
There is a famous law which says that a potential difference is produced across a conductor when it is exposed to a varying MF. But, how do you measure it to prove? It is quite practical.
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Magnetic induction in solenoid
I found an equation in theory about magnetic induction in a solenoid: $B_s=\mu_0 I n$. It should be magnetic induction for infinite length solenoid. I wonder if this is anyhow useful. Where can this ...
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2answers
77 views
What is the maximum power available from a magnetic field?
I just want to validate something I inferred from studying Griffiths (1999).
The instantaneous magnetic field $\vec{b}(t)$ at a distance $r$ from a long infinite conductor carrying a current $i(t)$ ...
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1answer
101 views
Is it possible to get energy from electrical wire using induction?
Pardon me if this is a stupid question but my physics courses are from a long long time ago and I was a teenager back then. ;)
Electricity in a wire generates electromagnetism, right?
Would it be ...
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131 views
What is the current induced in a straight wire when a magnetic field is turned from on to off?
Consider a straight wire which runs along the y-axis. A B-field exists which is uniform and only in the x-direction:
$$\vec{B}=(B(t),0,0)$$
The B-field at time $t_0$ is 'switched off' in ...
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2answers
85 views
What would result in a transformer that has its secondary wires disconnected from any circuit?
I am studying magnetism and I am curious as to what happens in a transformer that has its secondary output wires connected through a circuit versus one that doesn't.
My main questions (in the case of ...
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1answer
182 views
Basic magnet through a copper coil experiment - What if poles were rotated 90 degress
I was wondering what voltage or current, if any, would be produced if the basic magnet through a copper coil experiment had the poles rotated 90 degrees so north and south faced the top/bottom of the ...
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1answer
93 views
Does special relativity unify the two phenomena at the base of Faraday's flux law (was Feynman wrong in this case)?
Consider Faraday's flux law for the EMF generated in a conductor loop:
$$ \varepsilon = - \frac{d \phi}{dt},$$
where $\varepsilon$ is the EMF, and $\phi$ is the magnetic flux through the loop.
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3answers
217 views
What is the current through the lamp?
We have the following circuit:
A neon lamp and a inductor are connected in parallel to a battery of 1.5 $V$. The inductor has a 1000 loops, a length of $5.0 cm$, an area of $12cm^2$ and a ...
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2answers
156 views
locality vs non-locality
Suppose we have a circular loop of wire, and we put a long perfect solenoid inside it which is connected to an AC voltage source so that the magnetic field inside it starts to vary by time, does this ...
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1answer
139 views
Can an induction coil heat two layers of metal?
Imagine we have an induction coil which is strong enough to heat a sheet of metal. We can put a sheet of ferromagnetic metal close to the coil at distance $h_1$, and it gets heated to temperature ...
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2answers
290 views
Proving the consistency of Faraday's law of electromagnetic induction
Here is a question which frequently occurs on my school exam paper:
"Prove that Faraday's law of electromagnetic induction is consistent with the law of principle of conservation of energy." What ...
