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1 vote
0 answers
131 views

Coilgun projectile force calculation

Please excuse me if I am completely wrong because I am a 9th grader but I hopefully am able to explain briefly about my problem. I was trying to create a function to calculate the Force of an iron ...
0 votes
1 answer
126 views

What provides energy in mutual inductance to unconnected coil

In this mutual inductance setup: when current is passed through coil 1 the flux through coil 2 changes for a short amount of time which induces a current in coil 2 the direction of which, in ...
0 votes
1 answer
96 views

Forms of energy in a closed circuit with a coil

I am a bit confused. When i move a magnet through a coil thats in a closed circuit, what does my kinetic energy convert to? I assume I will create a magnetic field, and that magnetic field will create ...
0 votes
0 answers
122 views

Self-inductance, back EMF and energy stored in magnetic fields

First let's talk about self inductance. A current-carrying loop produces a magnetic field which in turn produces a flux through the loop. If this current is increased, the flux changes as the magnetic ...
0 votes
1 answer
97 views

How an inductor lose energy when pulling iron

I'm confusing with a problem. Consider an ideal inductor with a shorted circuit and no resistance and having a current through it. we know this current is constant while the inductor has no resistance ...
0 votes
1 answer
75 views

Energy stored in an Inductor is used to move electrons

I was reading about the energy stored in an Inductor and first of all I had the question that is this actually stored? The inductor produces a magnetic field which exerts a force on electrons. Isn't ...
-1 votes
1 answer
89 views

Why integration? [closed]

This is the expression of an energy stored in an inductor, i know it came from integrating inductance (as a constant) and current with respect to time, but my question is why it was integrated? What ...
0 votes
1 answer
749 views

Energy Loss in an Inductor

I have a question about an ideal inductor. I understand the induced EMF due to moving charge and the more turns of an idealized inductor the higher the non-conservative induced emf is opposing current....
1 vote
0 answers
56 views

Velocity of an Object Accelerated by an Inductor

I am currently trying to build a coil gun as a class project (for an introductory programming/electronics class), and I want to be able to determine the launch angle necessary to send an object a ...
2 votes
1 answer
841 views

Explanation of force amplification inside a solenoid

For a system being actuated by a motor, the force can be amplified by gearing. The energy is being used for force instead of distance, so it produces more torque but moves slower. For a system being ...
3 votes
2 answers
846 views

Energy stored in the magnetic field

While deriving energy density of a magnetic field via using an inductor, why dont we consider the energy stored outside of inductor also? As initially the field was there outside the inductor, (may ...
10 votes
5 answers
10k views

Magnetostatic energy density -- derivation without introducing inductance?

I was looking for a derivation of the expression for the energy density at any point in a static magnetic field. I do know that it is $$u_B=\dfrac {1}{2 \mu_0}\left|\mathbf{B}\right|^2,$$ I was just ...
2 votes
1 answer
237 views

How can we define the energy stored in a (conservative) force field?

I have come to know from my textbook that energy is stored in the E-field of a capacitor, in the B-field of an inductor and so on. Take the example of an inductor. The derivation bewilders me ...