Quite often, connecting wires carrying currents in opposite directions are twisted together in using electrical appliances. Explain how it avoids unwanted magnetic fields.

Two parallel wires carrying same current in the opposite direction will experience _________ .

The two long, straight wires carrying electric currents of 10A each in opposite directions. The separation between the wires is 5.0 cm. Find the magnetic field at a point P midway between the wires.

Two long and parallel street wires carrying current of 2A and 5A in the opposite direction are separated by a distance of 1 cm. Find the nature and magnitude of the magnetic force between them.

Two parallel wires P and Q placed at a separation d= 6 cm carry electric currents i_1= 5A and i_2= 2A in opposite directions as shown in figure. Find the point on the line PQ where the resultant magnetic field is zero.

Two parallel wires carry currents of 20A and 40A in opposite directions. Another wire carrying a current antiparallel to 20A is placed midway between the two wires. The magnetic force on it will be

A long straiht telephone cable contains six wires , each carrying a current of 0.5 A. The distance between the wires can be neglected. a. If the current in all six wires are in the same direction, what is the magnitude of the magnetic field 10 cm from the cable ? b. If four wires carry current in one direction and the other two in opposite directions, what is the field magnitude at 10 cm from the cable ?

Three coplanar parallel wires, each carrying a current of 10 A along the same direction, are placed with a separation 5.0 cm between the consecutive ones. Find the magnitude of the magnetic force per unit length acting on the wires.

Consider a coaxial cable which consists of an inner wire of radius a surrounded by an outer shell of inner and outer radii b and c respectively. The inner wire carries an electric current (i_0) and the outer shell carries an equal current in opposite direction. Find the magnetic field at a distance x from the axis where b.

The magnetic field at a point midway between two parallel long wires carrying currents in the same direction is 10 mu T. If the direction of the smaller current among them is reversed, the field becomes 30 mu T . The ratio of the larger to the smaller current in them is