Magnetics 4 Question 15
16. A wire of length $L$ metre carrying a current $i$ ampere is bent in the form of circle. The magnitude of its magnetic moment is …… in MKS units.
(1987, 2M)
Analytical & Descriptive Questions
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Answer:
Correct Answer: 16. $\frac{L^{2} i}{4 \pi}$
Solution:
- Let $R$ be the radius of circle. Then,
$$ \begin{gathered} 2 \pi R=L \quad \text { or } \quad R=\frac{L}{2 \pi} \\ M=i A=i \pi R^{2}=\frac{L^{2} i}{4 \pi} \end{gathered} $$
