A long straight wire carries a current of π amp. The magnetic field due to it will be 5×10−5 weber/m2 at what distance from the wire (in metre) ?
Answer & explanation
Correct answer: option 3
Magnetic field due to a long wire : B = \(\frac{\mu_{o}}{2\pi}\) \(\frac{I}{r}\)
I : current
r : distance
r = \(\frac{\mu_{o}}{2\pi}\) \(\frac{I}{B}\)
= 104 μ0