A region of uniform magnetic field, , is represented by the grey area of the box in the diagram. The magnetic field is oriented into the page.

A stream of protons moving at velocity is directed into the region of the magnetic field, as shown. Identify the correct path of the stream of protons after they enter the region of magnetic field.

Two parallel wires a distance apart each carry a current , and repel each other with a force per unit length. If the current in each wire is doubled to , and the distance between them is halved to , by what factor does the force per unit length change?

A solenoid is long and it is made up of turns of wire. How much current must run through the solenoid to generate a magnetic field of inside of the solenoid?

An infinitely long wire has a current of running through it. Calculate the magnetic field at a distance away from the wire.