Question

What is the function of choke

Answer 1

The choke, or inductor when used in flourescent lamps serves as an impedance, limiting the current through the lamp. Often the choke is really a transformer in addition to being a current limiting device, with a low voltage tap used to heat the cathodes in a flourescent lamp. An inductor can serve as a current limiting device with very low losses compared to a resistor.
Without choke maximum current flows in the fluorescent lamp, and with choke (which is a inductor )stored the current in the form of charge and reduces the value of maximum current and helps on starting, without choke , the lamps may get fused or never starts.