Question

A toroid of n turns, mean radius R and cross-sectional radius a carries current I. It is placed on a horizontal table taken as x-y plane. Its magnetic moment $\overrightarrow { \mathrm { M } }$

• A. Is non-zero and points in the z-direction by symmetry
• B. Points along the axis of the toroid ( $\vec { M } = M \hat { \phi }$ )
• C. Is zero, otherwise there would be a field falling as $\frac { 1 } { \mathrm { r } ^ { 3 } }$ at large distances outside the toroid
• D. Is pointing radially outwards.

Answer 1

Answer: (C)

Is zero, otherwise there would be a field falling as $\frac { 1 } { \mathrm { r } ^ { 3 } }$ at large distances outside the toroid

Answer 2

In a toroid magnetic field as in only confined inside the body of toroid in the form of concentric magnetic lines of force and outside the toroid magnetic