Single Choice

A current of $$\dfrac{1}{(4\pi)}$$ ampere is flowing in a long straight conductor. The line integral of magnetic induction around a closed path enclosing the current-carrying conductor is

A$${10}^{-7}Wb$$ $${m}^{-1}$$
Correct Answer
B$$4\pi \times{10}^{-7}Wb$$ $${m}^{-1}$$
C$$16{\pi}^{2} {10}^{-7}Wb$$ $${m}^{-1}$$
D$$zero$$

Solution

$$\oint { \vec { B } } \cdot d\vec { l } ={ \mu }_{ 0 }I$$

$$=4\pi \times {

10 }^{ -7 }\times \cfrac { 1 }{ 4\pi } $$

$$= { 10 }^{ -7 }Wb{ m }^{

-1 }$$

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