Question

The magnetic field a distance 2 cm from a long straight current-carrying wire is 2 × 10–5 t. the current in the wire is:

Answer 1

Current in the wire = 2 A

Explanation:

the magnetic field is given by

B= \frac{\mu i}{2\pi r}

μo= 4π x 10⁻⁷ Tm/A

i= current

r=0.02 m

B = magnetic field= 2 x 10⁻⁵ T

2 x 10⁻⁵= (4π x 10⁻⁷)(i) / (2π*0.02)

i=2 A