Question

Will a pair of parallel current-carrying wires exert forces on each other? 1. yes; the wires are electrically charged. 2. no; the magnetic field generated by the currents of the wires does not affect the wires themselves. 3. yes; the magnetic field generated by the current in one wire is perpendicular to the current in the other wire and vise versa. 4. no; the two wires attract each other by

Answer 1

Number 3.

When you have two parallel wire and the charges are moving, they create a magnetic field around the wire (right-hand rule, thumb points in the direction of current).

If you want the math, here ya go:

$\frac{F}{L} = \frac{4 \pi *10^{-7}II' }{2 \pi r}$

F: magnetic force on the wire, L: length of the wire I: current in one wire I': current in other wire r: distance of the wire.

As we can see, two wires that has current through it will generate a force on each other.