Question

If two streams of protons move parallel to each other in the same direction, then they.

Answer 1

Hint: A proton is a subatomic particle with the symbol p and a mass slightly less than a neutron. It has a positive electric charge of +1e elementary charge and a mass slightly less than a neutron. Protons and neutrons, each with a mass of around one atomic mass unit, are referred to together as "nucleons" (particles present in atomic nuclei).

Complete step by step answer:
A magnetic field is created by an electric current. Depending on their direction, the fields can attract or repel. Imagine your right thumb pointing in the direction of the current to identify the direction of the magnetic field on a wire. Your right hand's fingers will wrap themselves around the wire in the same direction as the magnetic field. When two currents run in opposing directions, you can tell that the magnetic fields are in the same direction and repel each other. The magnetic field will be opposite when the currents run in the same direction, and the wires will attract.
They will observe a length contraction of the cosmos along the direction of motion in the frame of reference of the travelling charges. If both wires' electrons are travelling in the same direction, they will see the same number of electrons in the other wire (because they are moving at the same speed.) They do, however, observe more protons. Electric charges that differ from one another attract each other. It's only a smidgeon of a difference in length, but there are a slew of costs.
Due to relativistic length contraction, the electrons will "see" a larger density of electrons in the other wire if the currents run in opposite directions. And the wires will resist each other.

Note:
Similarly, in a series circuit, if you have two parallel wires with current flowing in opposing directions, the magnetic fields of the two wires will be moving in the same direction at the point where they meet, repelling each other. Ampère was able to formulate what is known as Ampère's law to quantitatively characterise this sort of magnetic force between electric currents.