Science Buddies: "Ask an Expert"

How does different colored water make the water gain and retain thermal energy at different speeds? Why do darker colors like blue, black, and violet gain and retain thermal energy faster and longer than lighter colors like yellow, orange, and red? Would yellow water gain more thermal energy than plain water? What causes these changes? How come color has this effect and why? Please help me!

Hello,

Do you have any hypothesis for your project? Have you collected any background research articles yet? If not, please do so, and then post question regarding any revision needed for experimental procedure.

Hope this helps.

HostSha
Secondary School Teacher

i have a hypothesis already and i have done some research but i've looked for hours and i can't find very much info on this topic. all i can find is how we see those colors and how they reflect the color that we see and i know the darker colors gain more energy but i don't know why. i need the basics because i don't really understand the wavelength differences and how that effects it's atoms and the movement of it's electrons........ it's all really confusing to me but i really have done some research......do you know any sites that can help explain it to me better?? thanx

Bonjour NM02!
After doing some research for you myself, I quickly found this site and I think it is just great. It basically sorts out your exact experiment for you. Well here it is!http://www.fsec.ucf.edu/ed/sm2/solar-en ... -color.pdf.

Have a great day!

Ok. Start with what you do understand.

We perceive light moving at a certain wavelength as a color. The light enters the eyes, interacts with them and our brain spits out "purple".

Dark vs Bright though, is a matter of how much light, not so much what color it is.

If you think about it, a really "bright" surface is just reflecting more light than a "dark" surface, regardless of the color on the spectrum. White, in fact, is thought of as reflecting all colors, black as reflecting none.

If you think of it that way, without getting hung up on the spectral stuff (wavelengths, whether it is red or violet), it probably makes more sense.

This is very simplified, but....sunlight comes in.

Some of it is reflected. That energy won't heat up the water.

Some of it is absorbed (not reflected). That energy has to go somewhere...sunlight has energy, so it turns into heat.

If the water is highly reflective ("bright"), it won't heat up as fast.

If it is highly nonreflective ("dark") it should heat up faster.

Now it could be that some colors are more reflective in water than others, or it could be that you're seeing more "black" (ie, seeing dark blue, or forest green instead of sky blue, neon green etc) just because the water for some reason isn't reflecting.

I'm not sure how much this helps with your...but heating water from sunlight is all about how much it stops rather than reflecting. Maybe if you can take that concept and look at your results, it may help you with explaining what happened.

I don't really know the answer, but I think that light colors are absorbed faster because they are lighter. And not dark. I am sorry if I am wrong! I am in fifth. I am glad if it helped!

yes, listen to what bradleyshanrock-solberg said above because this is probably the clearest explanation you will ever get...

bradleyshanrock-solberg...good job

aznnerd666