Answer the following question:

Why is choke coil needed in the use of fluorescent tubes with A.C. mains? Why can we not use an ordinary resistor instead of the choke coil?

Choke coil needed in the use of fluorescent tubes with A.C. mains because choke coil reduces the voltage across the tube and doesn’t waste the power whereas while using ordinary resistor, it waste the power in form of heat dissipation. Therefore, we can’t use an ordinary resistor instead of choke coil.