Question

Two coils P and Q of radius R and 2R are lying in the same plane with their centres coinciding. find the magnitude and direction of the resultant magnetic field at the common centre if they respectively carry currents 3I and 2I in opposite directions.

Answer 1

Hey mate!!

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→ suppose magnetic field at first coil be B1 and second coil be B2.

→ B= μ°NI/2R (at center)

→ B1 = μ°3I/2R......at P

→ B2 = μ2I/4R........at Q

Since, Direction of Current is opposite

So NET magnetic field at center will be

B1-B2 = μ°I/2R(3-1)

Bnet = μ°I/R

Hope it helps :)

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