Questions tagged [electromagnetic-induction]

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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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Faraday's law in a ring

What role does the induced emf in Faraday's law play in generating current in a ring in which the magnetic flux is changing ?
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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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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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2answers
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What will happen if we place salt water on a induction cooker?

As we know that induction cooker works on the principal of induction of current in a conducting plate. So I just wanted to know what will happen if we place salt water in a plastic container on the ...
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Electrostatic induction

Is this a correct definition of electrostatic induction, The production of opposite charges on a neutral body when a charged body is brought near to it? I think it's not the production but ...
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0answers
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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 a ...
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3answers
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Conservation of energy in Lenz's law

When we bring opposite poles of two magnets together, they attract each other (or vice versa). Now, we can say that the kinetic energy gained by the magnets is due to the attractive force. Similarly, ...
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4answers
450 views

Induction cooker + superconductive pot [closed]

What will happen if I put a super-conductive object on an induction cooker, and turn the cooker on?
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1answer
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Why doe we not get a shock on induction cooker?

In induction cooking, eddy currents in cook-pot cause heat to be produced. But why do we not get a shock? Also, why is it that current is converted to heat while it has a good conductor(say, steel) ...
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2answers
946 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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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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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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6answers
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Direction of Current, according to Lenz's law, from induced EMF

My textbook (NCERT Physics Class 12th) has the following figure (Pg 212). The Arm PQ is moved to the left side thus decreasing the area of the rectangular loop. This results in a decrease in magnetic ...
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3answers
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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
534 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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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 $t_1$...
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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 ...
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What is the difference between induced and motional emf?

At least from their names, it seems motional emf is induced, so what's the difference?