Fluorescent tubes are fitted with a choke. The choke coils
- Asteps up the line voltage
- Bsteps down the line voltage
- Creduce current in the circuitCorrect
- Dchokes low frequency currents
Explanation
The correct option is C because a choke coil is an inductor used to reduce or control the electrical current in an AC circuit without wasting much power.
In a fluorescent tube circuit, the choke serves two main purposes. First, it provides a high voltage surge to initiate the gas discharge when the light is switched on. Second, once the tube is lit, the choke acts as a current limiter. Because fluorescent tubes have negative resistance, the current would increase indefinitely and destroy the tube if not restricted. The choke uses its inductive reactance to limit this current flow efficiently, ensuring the tube operates safely and consumes less power compared to using a standard resistor.
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