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:

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