Two concentric current loops lie in the same plane. The smaller loop has a radius of 2.9 cm and a current of 12 A. The bigger loop has a current of 20 A . The magnetic field at the center of the loops is found to be zero.
What is the radius of the bigger loop?

the radius of bigger loop is 4.83cm

Explanation:

Given that,

two concentric current loops

smaller loop radius = 2.9 cm

current in smaller loop = 12 A

current in the bigger loop = 20 A

magnetic field at the center of loop = 0

Radius of the bigger loop = ?

The equation for the magnetic field at the center of a circular loop is:

we have:

now,

the radius of bigger loop is 4.83cm

The radius is 4.833cm

Explanation:

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