The strength of the magnetic field at a point r near a long straight c – McqOptions

MCQOPTIONS

1.	The strength of the magnetic field at a point r near a long straight current carrying wire is B. The field at a distance \[\frac{r}{2}\] will be [MP PMT 1990]
A.	\[\frac{B}{2}\]
B.	\[\frac{B}{4}\]
C.	2B
D.	4B
Answer» D. 4B

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