The magnetic field created by a current-carrying wire is found by the Biot-Savart law The strength of the magnetic field created by current in a long straight wire is given by B = μ 0 I 2 π R (long straight wire) where I is the current, R is the shortest distance to the wire, and the constant μ 0 = 4 π…

The direction of the magnetic field created by a long straight wire is given by right-hand rule 2 (RHR-2): Point the thumb of the right hand in the direction of current, and the fingers curl in the direction of the… The force between two parallel currents I 1 and I 2 , separated by a distance r , has a magnitude per unit length given by F l = μ 0 I 1 I 2 π r

long straight wire — given by B = μ 0 I 2 π R (long straight wire) where I is the current, R is the shortest distance to the wire, and the constant μ 0 = 4 π…. force — attractive if the currents are in the same direction, repulsive if they are in opposite directions. center of a circular loop — given by B = μ 0 I 2 R (at center of loop) , where R is the radius of the loop. Biot-Savart law — an equation giving the magnetic field at a point produced by a current-carrying wire.