All Questions
Tagged with magnetic-fields electric-current
352
questions
0
votes
0
answers
28
views
Can field effect transistor s channel s varying depletion layers generate electric flux and control output current indirectly
Since magnetic field lines without need of contact attracts iron filing and drag them closer so that magnetic field line remain smallest.same analogy applied to field effect transistor ions in the ...
0
votes
0
answers
16
views
Force on current carrying loop due to non-uniform magnetic field
I was been taught that when there is a non-uniform magnetic field then the Force on a current carrying loop with Magnetic Moment M is F = M(dB/dx) where B is magnetic field.
I can't get hold of this ...
0
votes
0
answers
48
views
Force acting on an infinite wire with current inside a magnetic medium
I've recently stumbled on an electromagnetics problem that I don't quite understand.
There is an infinite wire carrying current I that is placed inside a medium with magnetic permittivity μ1. At a ...
1
vote
1
answer
90
views
Do twisted pair wires create a helical shaped magnetic field if parallel electrical currents are run through the two wires?
I would like to know if the shape of the magnetic field around twisted pair insulated wires will be a helical shaped magnetic field if both wires have parallel electrical current running through them.
...
- 478
2
votes
3
answers
90
views
Current density and units
I have a question about current densities. My understanding is that there are 3, volumic $(\vec{J})$ , surface $(\vec{K})$ and linear $(\vec{\lambda})$. The first question is, that if J is volumetric, ...
- 67
0
votes
1
answer
29
views
General Form of the Biot-Savart Law for anywhere on the $x$-Axis [closed]
This question is beyond me, and I have very little direction for solving it. I understand that the component of $\ B $ perpendicular to the $x$-axis is 0, and that the component parallel along the $x$-...
- 3
1
vote
1
answer
60
views
Forces on an elliptical current-carrying Loop
Consider a current-carrying elliptical 1-turn coil as shown in the picture below:
Is it true that due to forces from the current, the elliptical shape of the coil will tend to become circular?
- 21
1
vote
2
answers
42
views
Determinate the direction of the current of current-carrying wire by the right-hand rule
I have experienced a conundrum while using the right-hand rule to determine the direction of the current. I read a textbook that said: "Curl the fingers around the integration path..." ...
- 35
0
votes
0
answers
50
views
What logic is being used in Bleaney & Bleaney to prove the reciprocity theorem for mutual inductance?
I'm currently reading Bleaney & Bleaney 3rd Ed. On pg 136 they discuss the case of 2 coils. Their logic is as follows:
If a second coil is brought near to a coil carrying a current $I_1$, there ...
- 126
1
vote
2
answers
36
views
Force between two current carrying conductors
lets say I have two wires. each has a magnetic field due to its current. this magnetic field is present in the other wire causing a force in that other wire. Now I understand that changing the current ...
- 117
1
vote
3
answers
111
views
Does a single moving charge produce magnetic field in an empty universe?
If we have a singular charge in a universe and it is not stationary can it produce a magnetic field? Because even though it's moving there will be no relative motion and no electric force will act on ...
2
votes
1
answer
132
views
Potential difference in a ring
Basically in a circuit there is a cell with a positive and negative end, and current flows through it - electrons are pushed by negative electrode and attracted to the positive electrode. But if say a ...
- 137
0
votes
0
answers
57
views
I can’t figure out the magnetic field around a non-straight wire
Say I have a circuit where the wire has a shape defined by some closed
Parametric defined as $(X(t), Y(t), Z(t))$ (it is a loop), how do I calculate the entire magnetic field around the circuit?
1
vote
2
answers
48
views
Why does the force in a motor move perpendicularly instead of towards each other?
This may be a peculiar way of asking but given the image below:
Flemings left-hand rule
How does the wire experience a force upwards rather than being attracted directly to the magnet? If a current ...
- 11
0
votes
1
answer
87
views
Lorentz force separation from induction in rotating loop within AC magnetic field
I was wondering , is it possible to create a loop of any kind of geometry that could rotate in a non homogeneous AC magnetic field and have no net induction within the loop but only have current ...
- 91