# A Solenoid (single or multi turn) and forces

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1. Feb 25, 2017

### 1Keenan

Hi all,

I need help in understand what happen when a coil, let's say a solenoid with N turn (N = 1 or whatever) produces a very high magnetic field.
I know that the solenoid could explode, this means that there are forces on it, and I don't know how to calculate.
Can somebode helps me?
Can you provide any reference for this calculation?

Thank you

2. Feb 25, 2017

### Mausam

You told that B is high hence i is high.consequently more heat is generated which causes explosion. As far as calculations are concerned it depends on resistance, thermal conductivity and Melting point of the material.

3. Feb 25, 2017

### 1Keenan

so it does not depends on the magnetic field itself, but on the heating due to the current...
Can you please provide some reference?

4. Feb 25, 2017

### Mausam

Yes. You can refer any high school book on electrodynamics.And if you want formulas search "magnetic field due to current carrying coil"and "heating effects of current".
Hope it helps

5. Feb 25, 2017

### 1Keenan

thank you

but are you sure that there is no effect due to the magnetic field?
I mean solenoids for high field usually have a bulk to keep the structure all together, even if they don't melt

6. Feb 25, 2017

### 1Keenan

Hi again,

can you check this calculation, please?
I have:
Current (FWHM): I=2e5A
time of current pulse (FWHM) t=3nsec

For the conductor:
Resistance: 0.018473 Ohm
Volume: Vol=0.932 mm3
Mass: M=8.313e-6 Kg
Specific heat: Cs = 385 J7(Kg*Kekvin) [Specific heat of Copper]

I calculate:

Power: P=R*I^2=7.39e8 Watt
Heat (Joule): Q = P*t=2.217J
Termal Jump: DT = Q / (Cs*Mass) = 692.6 K

I see that temperature is crazy....