Question

why Tubelight's make noise after using somedays?

Answer 1

here are two sources
of noise in a tube light:

1. Choke
2. Luminaire

1. Choke: Tube light consists of a
choke to reduce the current flow to the tube, current is generally
controlled by using an inductor coil or a transformer. When the choke is used for many days the transformer inside gets faulty and lose resulting in magnetostriction effect in its core that produce a buzzing sound.
Increased sound also means that
choke coil is about to fail. In contrast if electronic choke is used sound is minimized.

2. Luminaire: Luminaire is commonly known as tube holder, it is where the choke is mount. It is generally made of ferrous material and when leakage
magnetic field of the choke acts on it, certain parts of the luminaire gets magnetized creating a mechanical stress. This stress produce the humming sound.

Answer 2

Here is the reason:
When we use choke for several days it just interrupts and change suddenly in current. So tubelights make noises after using it for some days.
Hope this helps you!