Why does hair get darker when wet?

Question

i think someone already asked this but it never rly got answered

Answer 1

The surface of the hair is rough, so it scatters light well. When light strikes dry hair, the light scatters back in many different directions. Water smooths out the rough surface. When the light strikes the wet surface, a small amount of light gets reflected off of the smooth water surface right away. As the remaining light penetrates deeper, the light scatters off of the rough hair surface and travels back towards the water surface. Because scattering the light results in random angle changes, a lot of the scattered light gets internally reflected by the water surface and never makes it out of the water. Therefore, when compared to dry hair, wet hair "absorbs" light therefore looks darker.

Answer 2

Actually the reason hair gets darker when wet is due to the fact that hair can absorb water, once the water is absorbed into the hair it creates a mutted look to the color present in the hair shaft. Thus making it less refective to light.

Answer 3

because it is soaked? Compare it to a washcloth. When a washcloth gets wet, it gets darker. When hair gets wet, it gets darker.