What Magnetic field is generated

[Vikas_Madhu]

If am using a flat spiral coil and giving sinusoidal voltage signal to it. i want to find the field generated at a point which is located at d cms from the flat spiral coil how can i get it? and also if am using another flat spiral coil at distance d cms what is the voltage induced in it..?

 

[Dale]

Unfortunately, for the geometry you describe I do not think that there is an exact solution. You will have to use the Biot-Savart law and integrate numerically.

http://en.wikipedia.org/wiki/Biot–Savart_law

 

[Vikas_Madhu]

Thank you DaleSpam,

Actually i thought of it but had doubt whether we can use it or not, if it is correct method to proceed or not..

 

[Dale]

The Biot-Savart law is an approximation for the magnetostatic case. Strictly speaking, your coil is not magnetostatic, but as long as the size of the coil divided by c is small relative to the period of your voltage then the approximation is fine.

 

[Vikas_Madhu]

Am confused little bit what do you mean when you are telling coil divided by c.. can you explain it clearly...

 

[Dale]

Suppose your coil is 1 m in diameter. 1 m / (299792458 m/s) = 3.3 ns So if the period of your sinusoidal voltage is much greater than 3.3 ns (i.e. frequency much < 300 MHz) then the approximation should be fine.

 

[Vikas_Madhu]

Yeah understood but the coil which am going to use will be 8cms, for that case we approximation will be fine nah

 

[Dale]

Yes, in that case you should be OK to use Biot-Savart up to 900 MHz or so.

 

[Vikas_Madhu]

K thank you sir, hope i will get positive result if i have doubt i will be back to you