What will happen if a.c voltage is applied between emitter and base 1 of ujt?

When AC voltage is applied between the emitter and base 1 of a Unijunction Transistor (UJT), the emitter becomes forward-biased relative to base 1. This can lead to the triggering of the UJT, causing it to conduct. As the emitter current increases, it will eventually reach a point where the transistor switches to the conducting state, resulting in a sharp increase in current flow through the device. The behavior can be used in applications such as oscillators and timing circuits.