Finding the Magnetic Flux of a Coil

[nokia8650]

See attached problem:

http://img72.imageshack.us/img72/4791/65321158jp4.th.jpg

The answer is 6.9 × 10−4 Wb - by multiplying the Area by the magentic flux density. Mq is, why does one not multiply this by 850 (number of turns) in order to find the answer.

Thanks

 

[sai_2008]

The flux that is coupled to the coil in dependent only on the area of the coil and the strength of the magnetic field that it is exposed to. In this case since it is oriented perpendicular to the field, all the area of the coil is exposed to the field.

It does not matter how many turns are there; the area of the coil as it "looks at the field" is still the same! Not 850, even if you had 8500000000... turns, the amount of flux cutting thru the coil is still 6.9e-4 Wb only :D