Answer:
the radius of bigger loop = 6 cm
Explanation:
given,
two concentric current loops
smaller loop radius = 3.6 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 = ?
[tex]B_t = B_1 + B_2[/tex]
[tex]0 = \dfrac{\mu_0I_1}{2R_1} +\dfrac{\mu_0I_2}{2R_2}[/tex]
now, on solving
[tex]\dfrac{I_1}{R_1} = \dfrac{I_2}{R_2}[/tex]
[tex]R_2 = I_2\dfrac{R_1}{I_1}[/tex]
= [tex]20\times \dfrac{3.6}{12}[/tex]
= 6 cm
hence, the radius of bigger loop = 6 cm
