Final answer:
The violet line in the spectrum tends to disappear because violet light is scattered more by the Earth's atmosphere than other colors, a phenomenon known as Rayleigh scattering.
Step-by-step explanation:
The question concerning why the violet line disappears from the spectrum can be attributed primarily to the scattering of violet light by the atmosphere, which is more significant than the scattering of other colors. This phenomenon is known as Rayleigh scattering, and it is the reason why the sky appears blue, as blue and violet have shorter wavelengths and are scattered more efficiently by the small gas molecules in the Earth's atmosphere.
When we consider atmospheric effects, the key factor in the disappearance of the violet line is its scattering more than other colors, making it less visible.
The violet line disappears from the spectrum because it is scattered more than other colors. When sunlight passes through Earth's atmosphere, the violet light is scattered by molecules in the air, causing it to lose intensity and be less visible to the human eye. This scattering phenomenon is also responsible for the blue color of the sky during the day.