What is the force between the two (AC) current carrying conductors?)

[rampriya1729]

what is the force between the two (AC) current carrying conductors??)

in case of dc currents,they repel or attract when the two conductors carry current in the same or opposite direction,what about two wires carrying ac currents.

 

[vanhees71]

That can be a difficult question to answer. As long as the distance of the wires is small compared to the typical wavelength \lambda=2 \pi c/\omega, where \omega is the angular frequency of the AC, you can evaluate the force from the mentary currents as if you had a stationary problem. This is known as the quasi-stationary approximation. In the general case, i.e., for quickly changing currents and/or large arrays of wires (antennae), you have to take into account retardation, i.e., you have to take into account the finite time an em. signal needs to take effect.