Investigating Voltage-Inductance Relationship

  • Thread starter Thread starter rahul.6sept
  • Start date Start date
  • Tags Tags
    Relationship
AI Thread Summary
Inductance remains constant unless the current exceeds the saturation current of the inductor, at which point the inductance decreases. The relationship between voltage, inductance, and current is defined by the equation V = L(di/dt), indicating that a change in current over time results in induced voltage. A hypothetical scenario involving a copper wire with changing radius raises questions about how this would affect inductance. When current approaches saturation, the inductance drops significantly, as explained in resources like Wikipedia. Understanding these principles is crucial for analyzing inductive systems in electrical engineering.
rahul.6sept
Messages
5
Reaction score
0
Dear all,

I would like to know how exactly the inductance varies with change in applied voltage with respect to time and if there is any mathematical relation for the same available.

Regards,
rc
 
Physics news on Phys.org
V = L\frac{di}{dt}

Where V is voltage, L is inductance, i is current and t is time. There has to be a change in current else there will be no induced Voltage. So the greater the change in current, the greater the induced Voltage. Simple as that.
 
rahul.6sept said:
Dear all,

I would like to know how exactly the inductance varies with change in applied voltage with respect to time and if there is any mathematical relation for the same available.

Regards,
rc

The inductance is constant, unless the current through the inductor exceeds the saturation current of the inductor.
 
yes it was a typo, should have been applied current and not applied voltage.

1) But what will be effect in inductance in case of a piece of copper wire (considering hypothetically) whose radius changes when current flows through it ?

2) Also would like to know regarding the reply of berkeman ... what actually happens when applied current exceeds the saturation current of the inductor.Regards,
rc
 
Last edited:
rahul.6sept said:
2) Also would like to know regarding the reply of berkeman ... what actually happens when applied current exceeds the saturation current of the inductor.

The wikipedia page gives a pretty good explanation of saturation. Basically the inductance drops for currents that approach ane exceed Isat...

http://en.wikipedia.org/wiki/Saturation_(magnetic )

.
 
Last edited by a moderator:
This is from Griffiths' Electrodynamics, 3rd edition, page 352. I am trying to calculate the divergence of the Maxwell stress tensor. The tensor is given as ##T_{ij} =\epsilon_0 (E_iE_j-\frac 1 2 \delta_{ij} E^2)+\frac 1 {\mu_0}(B_iB_j-\frac 1 2 \delta_{ij} B^2)##. To make things easier, I just want to focus on the part with the electrical field, i.e. I want to find the divergence of ##E_{ij}=E_iE_j-\frac 1 2 \delta_{ij}E^2##. In matrix form, this tensor should look like this...
Thread 'Applying the Gauss (1835) formula for force between 2 parallel DC currents'
Please can anyone either:- (1) point me to a derivation of the perpendicular force (Fy) between two very long parallel wires carrying steady currents utilising the formula of Gauss for the force F along the line r between 2 charges? Or alternatively (2) point out where I have gone wrong in my method? I am having problems with calculating the direction and magnitude of the force as expected from modern (Biot-Savart-Maxwell-Lorentz) formula. Here is my method and results so far:- This...
Back
Top