How does the power of a light bulb change during its long-term operation?

The power of the light bulb decreases, since when the light bulb operates, the tungsten filament evaporates, the cross-sectional area decreases, and the resistance increases.

Remember: The process of learning a person lasts a lifetime. The value of the same knowledge for different people may be different, it is determined by their individual characteristics and needs. Therefore, knowledge is always needed at any age and position.