How to generate a magnetic field

AI Thread Summary
To generate a magnetic field of 10 k A/m using a 1 mm copper wire and a 12V DC power supply, the current and number of turns must be optimized. The coil is overheating and causing short circuits, indicating that the resistance and current are too high for the setup. Solutions include adding a resistor or using a current-limiting power supply to prevent short circuits and overheating. Increasing wire size or implementing cooling methods, such as forced air, can also help manage heat. Ensuring proper insulation between layers of wire is crucial to avoid electrical issues.
androsidhom
Messages
1
Reaction score
0
dear all
i am trying to generate a magnetic field of intensity about 10 k A/m i have i 1 mm copper wire and a power supply 12v DC 18 amp max, i am winding the coil about 100 turn- 10 layers ( each layer with two ends)
the first problem that the coil heats up, also the resistance of the each layer is about 1.2 Ω and when i connect the solenoid to the power supply it makes a short circuit to the power supply
my questions are
1- is this no of turns and the amp available is sufficient to generate this intenisty of the magnetic field?
2- how to over come the short circuiting of the power supply?
3- how to over come the over heating of the solenoid?
4- is it much better to make the solenoid all connected together without separating each layer?
 
Physics news on Phys.org
1. This link should get you the equations and stuff you need to calculate your field. http://hyperphysics.phy-astr.gsu.edu/hbase/magnetic/solenoid.html#c3

2. You could try adding a resistor in the circuit or using a current limiting power supply.

3. Less current will reduce the heating, as would using a larger wire, as that would decrease the resistance. If you have no choice you could try to force air over it with a fan or water cool it. (Warning, be VERY careful about using water cooling to avoid a short.)

4. I'm not sure what you mean. Why are the layers seperated? Is your wire coated with an insulating material, or are you using bare copper wire?
 
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