Answer:
Gas atoms subjected to electricity emit bright lines.
Step-by-step explanation:
Gas atoms subject to electricity emit bright lines. This can be seen in fluorescent lamps, for example.
Fluorescent lamps work by ionizing atoms of argon gas and mercury vapor. After receiving an electric current, ionization occurs, at that moment the atoms are accelerated by the potential difference established between the lamp terminals and emit bright light and electromagnetic waves when they return to the natural state.