The magnetic field at the center of a 1.0-cm-diameter loop is 2.5 mT. a. What is the current in the loop?
b. A long straight wire carries the same current from part a. At what distance from the wire is the magnetic field 2.5 mT?

(a) The current in the wire is 19.89 A

(b) The distance from the wire is 0.159 cm

Explanation:

Given;

magnetic field, B = 2.5 mT

diameter of the wire, d = 1 cm

radius of the wire, r = 0.5 cm = 0.005 m

(a) The current in the wire is calculated as;

(b) The distance from the wire where the magnetic field is 2.5 mT is calculated as;

need to see circuit to get time constant