All Questions
11
questions
2
votes
1
answer
55
views
Does making a magnet move require more energy than a non-magnet?
I know that electric fields store energy, with their energy in an infinetesimal volume being proportional to $E^2$ at that point. I also know that a moving magnet creates an electric field (...
- 531
0
votes
1
answer
80
views
Is this a correct theoretical concept of a simple electric current generator?
As I think I somehow understand electromagnetic induction and after watching several experiments on YouTube with magnet pieces left to fall through coils which had connected ends to permit the ...
- 467
3
votes
4
answers
869
views
Why isn't Magnetic force doing any work on the rod?
Consider the situation given below :
The rod (of length $l$ and of some resistance "r") connecting the two rails is given a velocity $v$ in the direction shown. Now since this motion ...
- 8,220
0
votes
1
answer
95
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 ...
- 15
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 ...
- 453
1
vote
1
answer
693
views
Deriving magnetic field energy per unit volume for a wire
The magnetic energy per unit volume for an inductor can be derived from the formula:
$U=\frac{1}{2}L{I}^{2}$
But how to derive formula for energy per unit volume for a (long) wire. Since there is no ...
- 1,012
0
votes
1
answer
74
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
vote
2
answers
935
views
If I put an iron nail bear a magnet, a magnetic field would be induced in the iron nail
Now, the iron nail becomes a magnet without rubbing or any other energy-consuming process. Now, if I take the magnetized iron nail near other iron pieces, it would attract them and give them kinetic ...
- 323
7
votes
1
answer
2k
views
Motion in a time-dependent uniform magnetic field
Suppose you have an infinite solenoid generating an uniform magnetic field inside. The field is oriented along the solenoid axis : unit vector $\vec{\bf n}$. The field intensity varies linearly with ...
- 7,572
8
votes
6
answers
2k
views
How does an inductor store magnetic energy?
I am trying to figure out what the potential energy of an inductor with a current really means. In a capacitor, the energy stored works like this: if you let the plates attract each other, before ...
- 659
1
vote
1
answer
89
views
Does the wireless energy tranmission affect compass
Wireless energy using magnetic inductive coupling. So magnetic field will be affect around device. We use it to charge mobile device so I wonder if it will affect compass in our device
- 898